Coding-decoding is 85 of the 692 reasoning questions in the Punjab Police SI's papers, and it is the most mechanical topic in the whole paper. There is nothing to interpret. A word has been turned into something else by a fixed rule, and your only job is to recover the rule from the example you were given. The 85 split cleanly. 46 are letter coding, where a word becomes another string of letters or numbers. 31 are message coding, where whole sentences are coded and you work out one word's code by comparing sentences. 8 mix digits and symbols with a printed key. The message-coding 31 are worth noticing: twenty-nine of them use exactly one method, and that method takes about forty seconds once you have done it twice. They are, question for question, the cheapest marks in the reasoning section.
The teaching part above and below — the explanations, the figures and the worked examples on screen — is about 26 minutes. The collapsed question banks hold 85 solved past questions in all; working through every one of them takes roughly 3–4 hours. Do that across several sittings, not in one go.
Part 1 · Letter coding — align first, always
Shifts · opposite letters · rearrangement · numbers · a printed key
Whatever the rule turns out to be, the first action is identical: write the code immediately under the word, letter under letter. Only then ask what happened at each place. Now three quick checks settle which family you are in. Are the code's letters the same letters as the word's, in a new order? Then nothing was shifted — it is rearrangement. Is the code made of digits? Then letters became positions, and the only question is what was done to those positions. Otherwise it is a shift, and you read the shift at each place.
12 of the 46. Each place moves forward or back by some amount. The amount may be the same throughout (every letter +4), alternate by position (+2 on odd places, −2 on even), grow along the word (+1, +3, +5, +7), or even equal the letter's own position number in the word. Write all four shifts before concluding anything.
Every other shift-coding question (11)Tap to open
If in a certain code, LUTE is written as MUTE and FATE is written as GATE then how will BLUE be written in that code ? (SI 2016)
- 1CLUE
- 2GLUE
- 3FLUE
- 4SLUE
Show answer
Answer: 1 — CLUE
Compare the pairs letter by letter. LUTE → MUTE: only the first letter changes, L → M, one step forward. FATE → GATE: again only the first letter changes, F → G, one step forward. The rule is therefore 'move the first letter one place ahead in the alphabet and leave the rest alone'. Applying it to BLUE, B → C, giving CLUE. Options 2, 3 and 4 change the first letter by more than one step (B → G, B → F, B → S).
In a certain code, 'ACQUIRE' is written as 'YDOVGSC'. How will 'JOURNEY' be written as in that code? (SI 20 Aug 2021)
- 1HPSTLFW
- 2HPSSLFW
- 3HPSSFLW
- 4HPSSLFX
Show answer
Answer: 2 — HPSSLFW
Line the code up under the word and take the shift at each position: A→Y (−2), C→D (+1), Q→O (−2), U→V (+1), I→G (−2), R→S (+1), E→C (−2). The rule is simply −2 on the odd positions and +1 on the even positions. Apply it to JOURNEY: J−2 = H, O+1 = P, U−2 = S, R+1 = S, N−2 = L, E+1 = F, Y−2 = W → HPSSLFW. Option 1 (HPSTLFW) mishandles position 4, giving T instead of S; option 3 (HPSSFLW) swaps positions 5 and 6; option 4 (HPSSLFX) moves the last letter by −1 instead of −2.
In a certain code language, 'ZIP' is written as 'XGN' and 'PET' is written as 'NCR'. How will 'OUR' be written in that language? (SI 29 Jun 2023)
- 1NSP
- 2MSP
- 3NTQ
- 4MRO
Show answer
Answer: 2 — MSP
Every letter moves two places back in the alphabet. Z−2=X, I−2=G, P−2=N → XGN. P−2=N, E−2=C, T−2=R → NCR. Apply to OUR: O−2=M, U−2=S, R−2=P → MSP. Option 1 (NSP) shifts only the first letter by one; option 3 (NTQ) shifts every letter by one.
In a certain code language, 'JUTE' is written as 'L3V5', and 'SILVER' is written as 'U9N4G9'. How will 'GRIP' be written in that language? (SI 2 Jul 2023)
- 1I8K7
- 2I9J7
- 3I9K8
- 4I9K7
Show answer
Answer: 4 — I9K7
The rule alternates by position. Letters in odd positions move two places forward; letters in even positions are replaced by the digit sum of their alphabet number. Check JUTE: J(1st) → L (+2); U(2nd) = 21 → 2+1 = 3; T(3rd) → V (+2); E(4th) = 5 → 5. Gives L3V5. ✓ Check SILVER: S → U; I = 9 → 9; L → N; V = 22 → 4; E → G; R = 18 → 1+8 = 9. Gives U9N4G9. ✓ Now GRIP: G(1st) → I; R(2nd) = 18 → 9; I(3rd) → K; P(4th) = 16 → 1+6 = 7. So GRIP = I9K7. Option 1 (I8K7) mis-sums R, and option 3 (I9K8) mis-sums P as 8.
Using the same logic as applied for the first two pairs of terms, replace the question mark (?) with the appropriate term in the third pair. CAT - DCW, DOG - EQJ, BOY - ? (SI 3 Jul 2023)
- 1CQA
- 2DQB
- 3CQZ
- 4CQB
Show answer
Answer: 4 — CQB
The three positions are shifted forward by 1, 2 and 3. CAT: C + 1 = D, A + 2 = C, T + 3 = W, giving DCW. DOG: D + 1 = E, O + 2 = Q, G + 3 = J, giving EQJ. For BOY: B + 1 = C, O + 2 = Q, and Y + 3 runs past Z and wraps round to B, so the term is CQB. Option 3 (CQZ) is the trap — it stops the wrap one letter short at Z (Y + 1) — while option 1 wraps too far to A and option 2 mis-shifts the first letter.
GMTR is related to IJXM in a certain way based on the English alphabetical order. In the same way, FLUT is related to HIYO. To which of the following is MGSY related, following the same logic? (SI 3 Jul 2023)
- 1RIVS
- 2ODWT
- 3OIVT
- 4RDWS
Show answer
Answer: 2 — ODWT
Compare the letters position by position. G(7) → I(9) is +2; M(13) → J(10) is −3; T(20) → X(24) is +4; R(18) → M(13) is −5. The second pair obeys the same rule: F(6) → H(8) +2, L(12) → I(9) −3, U(21) → Y(25) +4, T(20) → O(15) −5. Apply +2, −3, +4, −5 to MGSY: M(13)+2 = O, G(7)−3 = D, S(19)+4 = W, Y(25)−5 = T. That gives ODWT. OIVT keeps only the first letter right; RIVS and RDWS start from a wrong shift on M.
In a code language, 'TWINE' is coded as WNWIH and 'WIRED' is coded as ZEIRG. How will 'BLACK' be coded in the same language? (SI 15 Jul 2023)
- 1ECLAN
- 2DDKZM
- 3FCKBN
- 4FBKZM
Show answer
Answer: 1 — ECLAN
Two things happen at once. The first and last letters move +3 in the alphabet; the three middle letters are rotated one place to the right. TWINE: T+3 = W, E+3 = H; middle W, I, N → N, W, I. Code = W NWI H = WNWIH. WIRED: W+3 = Z, D+3 = G; middle I, R, E → E, I, R. Code = Z EIR G = ZEIRG. BLACK: B+3 = E, K+3 = N; middle L, A, C → C, L, A. Code = E CLA N = ECLAN. DDKZM is what you get by shifting every letter and reversing — neither example supports that.
In a certain code language, ‘AGE’ is written as ‘CJG’ and ‘CAB’ is written as ‘EDD’. How will ‘EON’ be written in that language? (SI 15 Jul 2023)
- 1GRP
- 2FPP
- 3GSP
- 4GQP
Show answer
Answer: 1 — GRP
The three letter positions get different shifts: +2, +3, +2. AGE: A+2 = C, G+3 = J, E+2 = G → CJG. CAB: C+2 = E, A+3 = D, B+2 = D → EDD. EON: E+2 = G, O+3 = R, N+2 = P → GRP. GQP (option 4) shifts every letter by 2 and GSP shifts the middle by 4 — both ignore the uneven pattern.
In a certain code language, 'FACED' is coded as BCEAZ and 'CHIME' as YIMHA. How will 'FRESH' be coded in the same language? (SI 15 Jul 2023)
- 1BESRD
- 2BDTQE
- 3ADTRF
- 4AERQD
Show answer
Answer: 1 — BESRD
Split the five letters into the two outer ones and the middle three. Outer letters move 4 places back: FACED → F − 4 = B, D − 4 = Z. CHIME → C − 4 = Y (wrapping past A), E − 4 = A. Both match the first and last letters of the codes. Middle three rotate one place to the left: A, C, E → C, E, A ✓ and H, I, M → I, M, H ✓. Apply to FRESH: F − 4 = B, H − 4 = D; middle R, E, S rotates to E, S, R. Code = B + E S R + D = BESRD.
FOREIGN is related to JSVIMKR in a certain way based on the English alphabetical order. In the same way, HISTORY is related to LMWXSVC. To which of the following is JUSTIFY related, following the same logic? (SI 29 Jul 2023)
- 1NYMWXJC
- 2NWMYXJC
- 3NJYWXMM
- 4NYWXMJC
Show answer
Answer: 4 — NYWXMJC
Each letter moves 4 places forward in the alphabet. F+4=J, O+4=S, R+4=V, E+4=I, I+4=M, G+4=K, N+4=R gives JSVIMKR; the same check works for HISTORY → LMWXSVC. For JUSTIFY: J+4=N, U+4=Y, S+4=W, T+4=X, I+4=M, F+4=J, Y+4=C, so the code is NYWXMJC. Options 1 and 2 use the same seven letters but with the middle ones swapped out of order, which is the usual trap in this pattern.
In a certain code language, ‘PAPER’ is written as ‘QCSIW’, and ‘CLOTH’ is written as ‘DNRXM’. How will ‘LETTER’ be written in that language? (SI 31 Jul 2023)
- 1MHWXJX
- 2MGXXJX
- 3MGWXJX
- 4MGWWJX
Show answer
Answer: 3 — MGWXJX
Rule: each letter moves forward by its own position number in the word — 1st letter +1, 2nd +2, 3rd +3, and so on. Check: P+1=Q, A+2=C, P+3=S, E+4=I, R+5=W gives QCSIW; C+1=D, L+2=N, O+3=R, T+4=X, H+5=M gives DNRXM. LETTER has six letters, so L+1=M, E+2=G, T+3=W, T+4=X, E+5=J, R+6=X, i.e. MGWXJX. The tempting option 1 (MHWXJX) puts +3 on the second letter and +4 on the third, which breaks the progression.
5 of the 46. Each letter is replaced by its partner from the other end of the alphabet, position 27 − n. The tell is a code whose letters run in the reverse direction from the word's. Two of the five apply the rule to only part of the word — to the consonants only, or to the odd positions only — so check each place even after you have named the rule.
Every other opposite-letter coding question (4)Tap to open
In a certain code language, 'FACE' is written as 'UZXV', and 'LAMB' is written as 'OZNY'. How will 'ACTING' be written in that language? (SI 20 Jun 2023)
- 1ZXGRMT
- 2ZXGSMT
- 3ZXGRMS
- 4ZXHRMT
Show answer
Answer: 1 — ZXGRMT
Each letter is replaced by its opposite letter in the alphabet, i.e. position 27 − n (A↔Z, B↔Y, C↔X, ...). Check FACE: F(6) → 27 − 6 = 21 = U; A(1) → Z; C(3) → 24 = X; E(5) → 22 = V. That gives UZXV ✓. Check LAMB: L(12) → 15 = O; A → Z; M(13) → 14 = N; B(2) → 25 = Y. That gives OZNY ✓. Now apply it to ACTING: A(1) → Z, C(3) → X, T(20) → 27 − 20 = 7 = G, I(9) → 18 = R, N(14) → 13 = M, G(7) → 20 = T. So ACTING becomes ZXGRMT. All four options begin ZXG, so the item is decided by the last three letters; option 4 (ZXHRMT) slips on T → H instead of G, and options 2 and 3 slip on I and G respectively.
UNABLE is related to VMZYOF in a certain way based on the English alphabetical order. In the same way, WEALTH is related to SVZOGD. To which of the following is VICTIM related, following the same logic? (SI 29 Jun 2023)
- 1NRXGRE
- 2NXRGRE
- 3GRENXR
- 4GNXRER
Show answer
Answer: 1 — NRXGRE
Replace every letter by its opposite letter (A↔Z, B↔Y, …, i.e. position 27 − n), then interchange the first and the last letter of the result. UNABLE → opposites F, M, Z, Y, O, V = FMZYOV → swap the ends → VMZYOF. ✔ WEALTH → opposites D, V, Z, O, G, S = DVZOGS → swap the ends → SVZOGD. ✔ VICTIM → V→E, I→R, C→X, T→G, I→R, M→N gives ERXGRN → swap the ends → NRXGRE. Option 2 (NXRGRE) has the second and third letters interchanged, so it fails the opposite-letter step.
In a certain code language, ‘ARC’ is written as ‘Z9X’ and ‘RAIN’ is written as ‘I1R5’. How will ‘BALL’ be written in that language? (SI 1 Jul 2023)
- 1Y1O4
- 2Y1P3
- 3Y1O2
- 4Y1O3
Show answer
Answer: 4 — Y1O3
Two different treatments alternate by position in the word. Odd positions (1st, 3rd) → the opposite letter (A↔Z, i.e. 27 − position). Even positions (2nd, 4th) → the digit sum of the letter's own alphabet position. Check against ARC → Z9X: Letter · Place · Treatment · Code A · 1 · opposite of A · Z R · 2 · R = 18 → 1+8 · 9 C · 3 · opposite of C · X Check against RAIN → I1R5: R(1st) → I; A(2nd) = 1 → 1; I(3rd) → R; N(4th) = 14 → 1+4 = 5. ✓ Now BALL: B(1st) → Y; A(2nd) = 1 → 1; L(3rd) → O; L(4th) = 12 → 1+2 = 3. So BALL → Y1O3. Option 1 (Y1O4) is the trap — it writes the last L as the opposite-letter count or a miscounted digit sum.
In a certain code language, 'AB12' is written as 'ZYZY', and 'CD34' is written as 'XWXW'. How will 'EF56' be written in that language? (SI 15 Jul 2023)
- 1VVVV
- 2VUVU
- 3UUUU
- 4UVUV
Show answer
Answer: 2 — VUVU
Rule: every letter goes to its opposite letter (A↔Z, B↔Y, C↔X, D↔W, E↔V, F↔U), and every digit is first read as that position in the alphabet and then turned into its opposite too (1 → A → Z, 2 → B → Y, 3 → C → X, 4 → D → W). Check: AB12 → Z, Y, Z, Y ✓ and CD34 → X, W, X, W ✓. Now EF56: E → V, F → U, 5 → E → V, 6 → F → U, giving VUVU. UVUV reverses the order of the pair and VVVV/UUUU ignore the second letter, so all three fail the worked examples.
15 of the 46 — the largest family. Before any arithmetic, compare the letters themselves. If the code uses exactly the word's own letters, number the places 1-2-3-4-5 and describe the code in those numbers rather than in letters. BLAME → LBMAH is 2-1-4-3-5, with the last letter shifted +3. Written as numbers, the rule applies to the next word without any thought at all.
Every other rearrangement question (13)Tap to open
In a certain code language, if "HIBISCUS" is coded as BIHSISUC and "MARIGOLD" is coded as RAMGIDLO, then how will "GERANIUM" be coded in the same coding language? (SI 18 Aug 2021)
- 1REGINAMU
- 2RNEGAIMU
- 3RAEGNIMU
- 4REGNAMUI
Show answer
Answer: 4 — REGNAMUI
Split each eight-letter word into blocks of 3, 2 and 3 and reverse each block on the spot. MAR|IG|OLD becomes RAM|GI|DLO = RAMGIDLO ✓, and HIB|IS|CUS becomes BIH|SI|SUC = BIHSISUC ✓. Now GER|AN|IUM becomes REG|NA|MUI = REGNAMUI. Option 1 (REGINAMU) is the trap of reversing 3-3-2 instead of 3-2-3.
In the following two triads, each group of letters is related to the subsequent one following a certain logic. Select from the given options, the one which follows the same logic. Triad 1 : BRUT - RUBT - TSDR Triad 2 : DINS - INDS - KLFQ (SI 29 Jun 2023)
- 1TORN - ORTN – QORP
- 2BURP - URBP – WPDN
- 3FILE - ILEF – KJHC
- 4LENS - ENLS – CPJU
Show answer
Answer: 2 — BURP - URBP – WPDN
Two steps are at work. Step 1 — the first three letters rotate left, the fourth stays: BRUT → RUBT (BRU → RUB), DINS → INDS (DIN → IND). Step 2 — apply +2, −2, +2, −2 to the four letters: RUBT → (R+2)(U−2)(B+2)(T−2) = TSDR; INDS → (I+2)(N−2)(D+2)(S−2) = KLFQ. Test the options: 1. TORN → ORTN is correct, but ORTN should give QPVL, not QORP. 2. BURP → URBP is correct, and URBP gives (U+2)(R−2)(B+2)(P−2) = WPDN. Both steps hold. 3. FILE should rotate to ILFE, not ILEF — it fails at step 1. 4. LENS → ENLS is correct, but ENLS should give GLNQ, not CPJU.
In a code language, 'FETCH' is coded as HCQYF and 'GRAPE' is coded as EPXLG. How will 'JIVED' be coded in the same language? (SI 29 Jun 2023)
- 1DGSAJ
- 2EHTBK
- 3EGTAK
- 4DHTAJ
Show answer
Answer: 1 — DGSAJ
The rule has two parts: the first and last letters of the word swap places, and the three middle letters move back by 2, 3 and 4 places. FETCH → swap F and H → H E T C F → E−2 = C, T−3 = Q, C−4 = Y → HCQYF. ✔ GRAPE → swap G and E → E R A P G → R−2 = P, A−3 = X, P−4 = L → EPXLG. ✔ JIVED → swap J and D → D I V E J → I−2 = G, V−3 = S, E−4 = A → DGSAJ. Option 4 (DHTAJ) keeps the correct end swap but shifts the middle letters by −1, −3, −4, so it fails on the first middle letter.
In a code language, 'BANGLE' is coded as FNJRFH and 'NUMBER' is coded as SGEQZT. How will 'CLAMPS' be coded in the same language? (SI 3 Jul 2023)
- 1TRPEQI
- 2STQDRF
- 3RQUTDI
- 4PURQED
Show answer
Answer: 1 — TRPEQI
Reverse the word first, then shift the letters by 1, 2, 3, 4, 5, 6 in order. BANGLE reversed is ELGNAB; E+1 = F, L+2 = N, G+3 = J, N+4 = R, A+5 = F, B+6 = H, giving FNJRFH. Check on the second example: NUMBER reversed is REBMUN; R+1 = S, E+2 = G, B+3 = E, M+4 = Q, U+5 = Z, N+6 = T, giving SGEQZT. Apply it to CLAMPS: reversed it is SPMALC; S+1 = T, P+2 = R, M+3 = P, A+4 = E, L+5 = Q, C+6 = I, so the code is TRPEQI. Shifting without reversing produces the distractor spellings in options 2 to 4.
In a code language, 'CLAMP' is coded as LCMAK and 'BORED' is coded as OBERY. How will 'PIQUE' be coded in the same language? (SI 3 Jul 2023)
- 1JPUQS
- 2IPUQZ
- 3JQURP
- 4IQURJ
Show answer
Answer: 2 — IPUQZ
The first four letters are swapped in pairs and the fifth is moved 5 places back in the alphabet. CLAMP: C-L becomes L-C, A-M becomes M-A, and P − 5 = K, giving LCMAK. BORED: B-O becomes O-B, R-E becomes E-R, and D − 5 counts back past A to Y, giving OBERY. For PIQUE: P-I becomes I-P, Q-U becomes U-Q, and E − 5 wraps to Z, so the code is IPUQZ. Options 1 and 3 keep J instead of I, i.e. they shift the first letter as well; option 4 fails the pair swap.
In a code GLAZED is coded as LGWDDE and QUILTS is coded as UQEPST. How will EXPIRE be coded in the same language? (SI 9 Jul 2023)
- 1TREMLX
- 2XELMER
- 3XMLRED
- 4TMLEXR
Show answer
Answer: 2 — XELMER
Break each six-letter word into three pairs. GLAZED = GL, AZ, ED and its code LGWDDE = LG, WD, DE. The first pair is simply reversed (GL to LG) and so is the third (ED to DE). The middle pair is not reversed: A − 4 = W (counting back past A to W) and Z + 4 = D (counting past Z to D). Verify on QUILTS = QU, IL, TS to UQEPST = UQ, EP, ST: QU reverses to UQ, TS reverses to ST, and in the middle I − 4 = E, L + 4 = P. Now code EXPIRE = EX, PI, RE. Reverse the first pair: XE. Middle pair: P − 4 = L and I + 4 = M, giving LM. Reverse the last pair: ER. The code is XELMER. Option 3 (XMLRED) mixes up which middle letter moves back and which moves forward.
In a code language, 'GRAPH' is coded as HUFWG and 'FLECK' is coded as KOJJF. How will 'WAVED' be coded in the same language? (SI 14 Jul 2023)
- 1DDALW
- 2DEBLX
- 3EDALV
- 4EFBKW
Show answer
Answer: 1 — DDALW
The rule has two parts: the first and last letters of the word simply change places, and the three middle letters move forward by +3, +5 and +7 respectively. Check GRAPH: outer letters G and H swap, giving H at the front and G at the end. Middle letters R + 3 = U, A + 5 = F, P + 7 = W. Result H U F W G = HUFWG. Correct. Check FLECK: outer letters F and K swap, giving K at the front and F at the end. Middle letters L + 3 = O, E + 5 = J, C + 7 = J. Result K O J J F = KOJJF. Correct. Now WAVED: outer letters W and D swap, so D goes in front and W at the end. Middle letters A + 3 = D, V + 5 = A (V, W, X, Y, Z, A — the alphabet wraps round), E + 7 = L. Result: D D A L W. Option 3 (EDALV) shifts the outer letters instead of swapping them, and option 2 (DEBLX) uses the wrong middle shifts (+4 and +6) and moves the last letter forward to X instead of ending in W.
In a code language, 'PROBE' is coded as EBORR and 'PLUMB' is coded as BMULR. How will 'WOVEN' be coded in the same language? (SI 14 Jul 2023)
- 1NEVOW
- 2EVNOW
- 3ENVOY
- 4NEVOY
Show answer
Answer: 4 — NEVOY
Write the word backwards, and move the letter that was originally first two places forward in the alphabet. Check PROBE: reversed it is E B O R P, and the original first letter P becomes P + 2 = R, so the code is E B O R R = EBORR. Correct. Check PLUMB: reversed it is B M U L P, and P + 2 = R, giving B M U L R = BMULR. Correct. Now WOVEN: reversed it is N E V O W, and the original first letter W becomes W + 2 = Y, so the code is N E V O Y. Option 1 (NEVOW) is a plain reversal with the +2 step left out — that is the trap, since both worked examples happen to start with P and only the last letter of the code reveals the shift.
In the following two triads, each group of letters is related to the subsequent one following a certain logic. Select from the given options, the one which does NOT follow the same logic. Triad 1 : CRAB - BARC - DDVH Triad 2 : SINK - KNIS - MQMX (SI 15 Jul 2023)
- 1GRIP - PIRG – RLVL
- 2RUST - TSUR – VVXV
- 3BART - TRAB – VUEG
- 4MONK - KNOM – MQSR
Show answer
Answer: 2 — RUST - TSUR – VVXV
Two rules chain together. Rule 1: the second group is the first group reversed. CRAB → BARC, SINK → KNIS. Rule 2: the third group comes from the second by shifting its successive letters +2, +3, +4, +5. Check: BARC → B+2 = D, A+3 = D, R+4 = V, C+5 = H = DDVH ✓. KNIS → K+2 = M, N+3 = Q, I+4 = M, S+5 = X = MQMX ✓. Now test the options: GRIP → PIRG ✓; PIRG → P+2 = R, I+3 = L, R+4 = V, G+5 = L = RLVL ✓. BART → TRAB ✓; TRAB → T+2 = V, R+3 = U, A+4 = E, B+5 = G = VUEG ✓. MONK → KNOM ✓; KNOM → K+2 = M, N+3 = Q, O+4 = S, M+5 = R = MQSR ✓. RUST → TSUR ✓, but TSUR → T+2 = V, S+3 = V, U+4 = Y, R+5 = W = VVYW, while the option prints VVXV. The reversal is correct in all four, so only the shift step separates them.
In a code language, 'PLACE' is coded as ECFLP and 'FINER' is coded as RESIF. How will 'CABLE' be coded in the same language? (SI 29 Jul 2023)
- 1ANGLE
- 2DANGL
- 3GLADE
- 4ELGAC
Show answer
Answer: 4 — ELGAC
Reverse the word, then move the middle (third) letter 5 places forward. PLACE reversed is ECALP; the middle letter A + 5 = F, giving ECFLP. FINER reversed is RENIF; the middle letter N + 5 = S, giving RESIF. For CABLE: reversed it is ELBAC; the middle letter B + 5 = G, giving ELGAC. The trap is to reverse only and stop at ELBAC, or to pick GLADE, which is merely an anagram of the letters.
In a code language, 'WALKED' is coded as DEOOAW and 'ENJOYS' is coded as SYMSNE. How will 'FRIGHT' be coded in the same language? (SI 31 Jul 2023)
- 1FTGRES
- 2TKHFLR
- 3THLKRF
- 4FSHLKT
Show answer
Answer: 3 — THLKRF
The rule has two halves. The outer letters simply swap in pairs: 1st with 6th and 2nd with 5th. The middle two letters stay in place but move forward in the alphabet — the 3rd letter by +3 and the 4th letter by +4. Check on WALKED: 1st and 6th give D and W, 2nd and 5th give E and A, L+3 = O, K+4 = O, so DEOOAW. Check on ENJOYS: S and E, Y and N, J+3 = M, O+4 = S, so SYMSNE. Apply to FRIGHT (F R I G H T): 1st and 6th give T and F, 2nd and 5th give H and R, I+3 = L, G+4 = K, giving T H L K R F. Option 2 (TKHFLR) is the trap for anyone who only reverses the word and then shuffles at random; the plain reversal THGIRF is not an option at all.
In a certain code language, ‘AID’ is written as ‘EHB’ and ‘URN’ is written as ‘OQV’. How will ‘INK’ be written in that language? (SI 31 Jul 2023)
- 1JMJ
- 2LOJ
- 3JML
- 4LMJ
Show answer
Answer: 4 — LMJ
First reverse the word, then shift the three letters by +1, -1, +1. AID reversed is DIA: D+1 = E, I-1 = H, A+1 = B, giving EHB. URN reversed is NRU: N+1 = O, R-1 = Q, U+1 = V, giving OQV. INK reversed is KNI: K+1 = L, N-1 = M, I+1 = J, giving LMJ. Option 1 (JMJ) is what you get if you forget to reverse the word first.
In a code language, 'TRUNK' is coded as RTNUN and 'BLAZE' is coded as LBZAH. How will 'QUOTH' be coded in the same language? (SI 31 Jul 2023)
- 1UQSPH
- 2UPQOH
- 3UPQST
- 4UQTOK
Show answer
Answer: 4 — UQTOK
Rule: take the five letters in pairs — swap letters 1 and 2, swap letters 3 and 4, and shift the fifth letter forward by 3. Check: TRUNK → TR becomes RT, UN becomes NU, K+3=N, giving RTNUN; BLAZE → LB, ZA, E+3=H, giving LBZAH. For QUOTH: QU becomes UQ, OT becomes TO, H+3=K, giving UQTOK. Option 2 (UPQOH) leaves the last letter unshifted and scrambles the middle pair.
11 of the 46. The letters are replaced by their alphabet positions and then something simple is done. In the SI's eleven that something is: the positions added; the sum doubled; each position reduced to its digit sum; each position cut by a constant; or the numbering run backwards, A = 26 down to Z = 1 — which is the opposite-letter rule in numeric clothing. Count the digits in the code: a short code means a sum, a long one means each letter was converted separately.
Every other letter-to-number question (10)Tap to open
In a certain code language, 'CUT' is coded as '88' and 'NUT' is coded as '110'. How will 'BUT' be coded in that same language? (SI 19 Aug 2021)
- 184
- 286
- 343
- 490
Show answer
Answer: 2 — 86
Add the alphabet positions of the letters and double the total. CUT = 3 + 21 + 20 = 44, and 44 × 2 = 88. NUT = 14 + 21 + 20 = 55, and 55 × 2 = 110. Both given codes fit, so the rule is confirmed. BUT = 2 + 21 + 20 = 43, and 43 × 2 = 86. Option 3 (43) is exactly the trap: it is the plain sum, with the doubling step forgotten.
If 'PLAYER' is coded as '731759', then 'MUNICIPALITY' will be coded as ______. (SI 19 Aug 2021)
- 1435939713920
- 2435939713827
- 3435939711927
- 4435939713927
Show answer
Answer: 4 — 435939713927
Each letter becomes the digit sum of its position in the alphabet. Check on PLAYER: P is 16 and 1 + 6 = 7; L is 12 and 1 + 2 = 3; A is 1; Y is 25 and 2 + 5 = 7; E is 5; R is 18 and 1 + 8 = 9. That spells 731759, the code given. Now do MUNICIPALITY letter by letter: M 13 → 4, U 21 → 3, N 14 → 5, I 9 → 9, C 3 → 3, I 9 → 9, P 16 → 7, A 1 → 1, L 12 → 3, I 9 → 9, T 20 → 2, Y 25 → 7. The code is 435939713927. All four options share the first six digits, so the work is in the tail. Option 3 turns the P into 1, option 2 turns the L into 8 and option 1 ends the Y as 0.
In a certain code language, 'PLAN' is coded as 11-15-26-13. How will 'ACID' be coded in that language? (SI 20 Aug 2021)
- 126-23-19-22
- 21-3-9-4
- 31-9-3-4
- 426-24-18-23
Show answer
Answer: 4 — 26-24-18-23
Find the rule from PLAN. P is the 16th letter and is coded 11; L is 12th and is coded 15; A is 1st and is coded 26; N is 14th and is coded 13. In every case code = 27 − (position of the letter), i.e. each letter is replaced by the position of its opposite letter counted from Z (A↔Z = 26, B↔Y = 25, and so on). Apply it to ACID: A = 1 → 27 − 1 = 26; C = 3 → 27 − 3 = 24; I = 9 → 27 − 9 = 18; D = 4 → 27 − 4 = 23. The code is 26-24-18-23. Option 2 (1-3-9-4) is the trap — it gives the plain forward positions and ignores the reversal, and option 3 is the same forward positions with two of them swapped.
In a certain code language, 'BAG' is written as '101' and 'CAB' is written as '37'. How will 'BAD' be written in that code language? (SI 16 Oct 2022)
- 165
- 250
- 3122
- 482
Show answer
Answer: 2 — 50
Replace each letter by its alphabet position and look for one rule that fits both given codes. BAG → B = 2, A = 1, G = 7, sum = 2 + 1 + 7 = 10. And 10^2 + 1 = 100 + 1 = 101 ✓ CAB → C = 3, A = 1, B = 2, sum = 3 + 1 + 2 = 6. And 6^2 + 1 = 36 + 1 = 37 ✓ So the code is (sum of letter positions)^2 + 1. BAD → B = 2, A = 1, D = 4, sum = 2 + 1 + 4 = 7, and 7^2 + 1 = 49 + 1 = 50. The rule is forced, not guessed: searching all rules of the form a x (sum)^2 + b x (sum) + c that reproduce both 101 and 37 gives exactly one solution, a = 1, b = 0, c = 1, so 50 is the only value this code can give BAD. None of the near-miss rules (sum of squares, sum of cubes, product of positions) reproduces both given codes at all. Why the others fail: 65 = 8^2 + 1 would need a letter sum of 8, 82 = 9^2 + 1 a sum of 9, and 122 = 11^2 + 1 a sum of 11 — but BAD sums to 7.
In a certain code language, 'FEAR' is coded as '18-6-5-1' and 'GONE' is coded as '5-7-15-14'. How will 'HANG' be coded in the same language? (SI 20 Jun 2023)
- 17-8-1-14
- 214-1-8-7
- 38-7-1-14
- 414-7-8-1
Show answer
Answer: 1 — 7-8-1-14
Write each word's letters with their alphabet positions, then see the order in which the code lists them. GONE = G(7), O(15), N(14), E(5); the code is 5-7-15-14 = E, G, O, N. So the last letter is moved to the front and the rest follow — a rotation to the right by one place. Check on FEAR = F(6), E(5), A(1), R(18): rotating right gives R, F, E, A = 18-6-5-1, which is exactly the code given. Apply to HANG = H(8), A(1), N(14), G(7): rotate right to G, H, A, N = 7-8-1-14. Option 3 (8-7-1-14) is the tempting one — it keeps H first and only swaps the first two values — but that does not match the rotation seen in both examples.
In a certain code language, 'HEAR' is coded as '5-8-18-1' and 'PLUG' is coded as '12-16-7-21'. How will 'SHIP' be coded in the same language? (SI 21 Jun 2023)
- 18-19-9-16
- 29-19-8-16
- 37-18-15-8
- 48-19-16-9
Show answer
Answer: 4 — 8-19-16-9
Each letter is replaced by its alphabet position, and then the letters are taken in the order 2, 1, 4, 3 — that is, the two letters of each pair swap places. HEAR = H(8), E(5), A(1), R(18). Swapping within each pair gives E, H, R, A = 5-8-18-1 ✓ PLUG = P(16), L(12), U(21), G(7). Swapping gives L, P, G, U = 12-16-7-21 ✓ SHIP = S(19), H(8), I(9), P(16). Swapping gives H, S, P, I = 8-19-16-9. Option 1, 8-19-9-16, is the trap: it swaps the first pair but leaves the second pair alone.
In a certain code language, 'EVIL' is coded as '3-20-7-10' and 'DONE' as '2-13-12-3'. How will 'FILM' be coded in the same language? (SI 2 Jul 2023)
- 14-7-10-11
- 26-9-12-13
- 34-7-12-11
- 46-7-10-13
Show answer
Answer: 1 — 4-7-10-11
Each letter becomes (its alphabet position − 2). Check: E(5)→3, V(22)→20, I(9)→7, L(12)→10; D(4)→2, O(15)→13, N(14)→12, E(5)→3. Both samples obey it. FILM: F(6)→4, I(9)→7, L(12)→10, M(13)→11, i.e. 4-7-10-11. Option 2 is the plain position with no shift and option 3/4 shift only some letters.
In a certain manner, 6 MRP is related to 216 RTO. Similarly, 7 SVX is related to 343 ZXU. Using the same logic, to which of the following is 5 LPG related? (SI 14 Jul 2023)
- 1525 IRN
- 225 IRN
- 3125 NRI
- 4125 IRN
Show answer
Answer: 4 — 125 IRN
Two things happen. The number is cubed: 6^3 = 216 and 7^3 = 343, so 5 becomes 5^3 = 125. That already kills options 1 (525) and 2 (25). For the letters, reverse the group first and then move every letter two places forward. MRP reversed is PRM, and P → R, R → T, M → O gives RTO. Check on the second pair: SVX reversed is XVS, and X → Z, V → X, S → U gives ZXU. Apply it to LPG: reversed it is GPL, and G → I, P → R, L → N gives IRN. So 5 LPG goes with 125 IRN. Option 3 has the right letters in the wrong order because the reversal was applied twice.
In a certain code language, 'COVISHIELD' is coded as '106' and 'COVAXIN' is coded as '88'. How will 'VACCINATION' be coded in that language? (SI 29 Jul 2023)
- 193
- 297
- 3109
- 4111
Show answer
Answer: 4 — 111
The code is the sum of the alphabetical positions of the letters. COVISHIELD = 3 + 15 + 22 + 9 + 19 + 8 + 9 + 5 + 12 + 4 = 106, and COVAXIN = 3 + 15 + 22 + 1 + 24 + 9 + 14 = 88, so the rule holds. For VACCINATION = 22 + 1 + 3 + 3 + 9 + 14 + 1 + 20 + 9 + 15 + 14 = 111. The near miss is 97, which is what you get if one of the two C's (3) or the repeated I/N is dropped while adding.
In a certain code language, ‘CAR539’ is written as ‘319ECI’, and ‘BAT368’ is written as ‘212CFH’. How will ‘DOLL123’ be written in that language? (SI 29 Jul 2023)
- 16433ABC
- 24633CBA
- 34633ACB
- 44633ABC
Show answer
Answer: 4 — 4633ABC
Letters and digits swap roles. Each letter becomes its alphabet position, reduced to a single digit by adding the digits; each digit becomes the letter at that position. The order of the parts is kept — letters first, then digits. CAR539: C = 3, A = 1, R = 18 → 1 + 8 = 9, giving 319; then 5 → E, 3 → C, 9 → I, giving ECI. So ‘319ECI’. Correct. BAT368: B = 2, A = 1, T = 20 → 2 + 0 = 2, giving 212; then 3 → C, 6 → F, 8 → H, giving CFH. So ‘212CFH’. Correct. DOLL123: D = 4, O = 15 → 1 + 5 = 6, L = 12 → 1 + 2 = 3, L = 3, giving 4633; then 1 → A, 2 → B, 3 → C, giving ABC. The code is 4633ABC. Option 1 has the digit block in the wrong order, and options 2 and 3 scramble the letter block.
Three questions supply the mapping outright — STAR = 1234, so S = 1, T = 2, A = 3, R = 4 — and ask you to code a different word from it. There is no rule to find. Write the dictionary in the margin, then substitute. The only way to lose the mark is to skip writing it down.
All three, solved (3)Tap to open
In a certain code language, B is written as D, E is written as G, I is written as J, L as N, R as S, T as V, and Y as Z. How will 'LIBERTY' be written in that language? (SI 18 Aug 2021)
- 1NJDGSVZ
- 2NJDGSVX
- 3NJDESVZ
- 4NJBGSVZ
Show answer
Answer: 1 — NJDGSVZ
The key is handed to you letter by letter, so no rule needs to be guessed — just substitute in order. LIBERTY has seven letters: L → N, I → J, B → D, E → G, R → S, T → V, Y → Z, which spells NJDGSVZ. It is worth noticing why the shifts are not uniform: B, E, L and T move forward two places while I, R and Y move only one, because each letter is replaced by the next letter that is not itself in the list of coded letters. Option 4 leaves B uncoded, option 3 leaves E uncoded, and option 2 sends Y to X (one letter back) instead of Z.
In a certain code language, if STAR is written as 1234 and TORE is written as 2546, then how will OATS be written in the same language? (SI 20 Jun 2023)
- 15321
- 21235
- 32351
- 45231
Show answer
Answer: 1 — 5321
Match the words letter by letter against their codes. STAR = 1234 gives S = 1, T = 2, A = 3, R = 4. TORE = 2546 gives T = 2 (consistent), O = 5, R = 4 (consistent), E = 6. Now substitute into OATS: O = 5, A = 3, T = 2, S = 1, i.e. 5321. Option 4 (5231) is the trap for anyone who keeps the digits of STAR in order after the O; but the digits must follow the letters of OATS in their own order.
In a certain code language, TOWEL is written as 12345 and WELCOME is written as 3456284. How will COOL be written in the same language? (SI 2 Jul 2023)
- 16235
- 26225
- 33224
- 46224
Show answer
Answer: 2 — 6225
Line the letters up with their digits. TOWEL = 12345 gives T=1, O=2, W=3, E=4, L=5. WELCOME = 3456284 gives W=3, E=4, L=5, C=6, O=2, M=8, E=4 — consistent with the first word and adding C=6 and M=8. Now COOL: C=6, O=2, O=2, L=5 → 6225. Option 4 (6224) mis-codes L as 4, and option 1 (6235) mis-codes the second O as 3.
Part 2 · Message coding — one method, 29 questions
Compare the sentences in pairs and read off what they share
You are given three or four coded sentences. The codes are deliberately not in word order, so matching the first code word to the first English word is exactly the mistake the question is built on. The method ignores order completely. Take any two sentences that have exactly one word in common. Their codes will then have exactly one code word in common, and those two must be each other. Write that pair down. Do the same for the next overlapping pair. Two or three such pairs are always enough to answer anything the question asks. This is why these questions come in twos — the same set of sentences carries questions 43 and 44 in almost every SI paper. Build the dictionary once; the second question is free.
- Find the overlap
- Match the codes
- Repeat
- Eliminate
If two sentences share two words, their codes share two codes and you cannot tell which is which. Skip that pair and find one that overlaps in exactly one word — there is always one.
Every other message-coding question (27)Tap to open
In a certain code, language, ‘1, 2, 3’ means ‘bright little boy’, ‘1, 4, 5’ means ‘tall big boy’ and ‘6, 3, 7’ means ‘beautiful little flower’. Which numerical in that language means ‘bright’ ? (SI 2016)
- 17
- 22
- 36
- 45
Show answer
Answer: 2 — 2
Compare the statements in pairs and look for what they share. - Statement 1 (1, 2, 3 = bright little boy) and statement 2 (1, 4, 5 = tall big boy) share exactly one numeral, 1, and exactly one word, boy. So 1 = boy. - Statement 1 and statement 3 (6, 3, 7 = beautiful little flower) share exactly one numeral, 3, and exactly one word, little. So 3 = little. - In statement 1 the numerals are 1, 2, 3 and the words are bright, little, boy. With 1 = boy and 3 = little, the only pairing left is 2 = bright. A program that tried every possible assignment of the seven words to the seven numerals confirmed that 'bright' must be 2 in every assignment that satisfies all three statements.
Which of the following is the code for 'it'? (SI 20 Jun 2023)
- 1gah
- 2sem
- 3tor
- 4jar
Show answer
Answer: 3 — tor
Compare the statements pairwise. Statements 1 and 2 share only the word 'is' and only the code 'jar', so is = jar. Statements 1 and 3 share 'is' and 'dancing' and the codes 'jar' and 'gah', so dancing = gah. Statements 2 and 3 share 'is' and 'bird' and the codes 'jar' and 'sem', so bird = sem. What is left in statement 1 is peacock = par, in statement 2 chirping = gav, and in statement 3 It = tor. So 'it' is coded as tor. Option 4 (jar) is the trap, because jar appears in all three sentences — that is exactly why it must be 'is', the only word common to all three.
Which of the following is the code for 'bird'? (SI 20 Jun 2023)
- 1sem
- 2tor
- 3jar
- 4gav
Show answer
Answer: 1 — sem
Compare the statements pairwise. Statements 1 and 2 share only the word 'is' and only the code 'jar', so is = jar. Statements 1 and 3 share 'is' and 'dancing' and the codes 'jar' and 'gah', so dancing = gah. Statements 2 and 3 share 'is' and 'bird' and the codes 'jar' and 'sem', so bird = sem. What is left in statement 1 is peacock = par, in statement 2 chirping = gav, and in statement 3 It = tor. So 'bird' is coded as sem. Option 4 (gav) is the trap: gav occurs only in the 'Bird is chirping' sentence, but 'bird' also occurs in sentence 3, where gav is absent, so gav must be chirping.
Which of the following is the code for 'birds'? (SI 21 Jun 2023)
- 1lo
- 2ae
- 3ke
- 4po
Show answer
Answer: 2 — ae
Compare the statements that share the word. 'Colourful chirping birds' = 'ae lo po' and 'Birds in sky' = 'ja ke ae'. The only word common to the two English phrases is 'birds', and the only code common to the two code strings is 'ae'. So birds = ae. 'lo' and 'po' are the codes for colourful and chirping in some order, and 'ke' belongs to 'in'.
Which of the following is the code for 'sky'? (SI 21 Jun 2023)
- 1ae
- 2ho
- 3ja
- 4re
Show answer
Answer: 3 — ja
Take the two statements containing 'sky'. 'Beautiful blue sky' = 'ho re ja' and 'Birds in sky' = 'ja ke ae'. Their only common English word is 'sky' and their only common code is 'ja', so sky = ja. Option 1 (ae) is the code for birds, already fixed by the same pair of statements.
How will 'I' be coded in that language? (SI 29 Jun 2023)
- 1dag
- 2don
- 3ras
- 4par
Show answer
Answer: 1 — dag
Compare the sentences two at a time and match the common word with the common code. 'I will go' = par dag ras and 'Will it rain' = aem don par share only the word 'will' and only the code 'par', so will = par. 'I will go' = par dag ras and 'She shall go' = ras kar jog share only the word 'go' and only the code 'ras', so go = ras. In the first sentence par and ras are now used up, so the remaining code dag must stand for 'I'. 'don' belongs to the second sentence, which does not contain 'I' at all, so option 2 cannot be right.
Which of the following can be the code for 'rain'? (a) par (b) don (c) aem (d) kar (e) dag (SI 29 Jun 2023)
- 1(d)
- 2(a)
- 3(b) or (c)
- 4(e)
Show answer
Answer: 3 — (b) or (c)
From the overlaps, will = par (common to the first two sentences) and go = ras (common to the first and third). 'Will it rain' = aem don par. Removing par, which stands for 'will', leaves aem and don for 'it' and 'rain'. No other sentence contains either 'it' or 'rain', so there is nothing to separate the two codes; 'rain' can be don or aem, i.e. (b) or (c). That is also why the question says 'can be' rather than 'is'. (a) par is already 'will', (e) dag is 'I' from the first sentence and (d) kar belongs to the third sentence, which has no word 'rain'.
What is the code for 'moon'? (SI 1 Jul 2023)
- 1bo
- 2dv
- 3sh
- 4gl
Show answer
Answer: 2 — dv
Compare the statements two at a time; the word they share must map to the code they share. - Statements 1 and 2 share the word light and the code pu → light = pu. - Statements 1 and 3 share the word sun and the code gl → sun = gl. - Statements 2 and 3 share the word moon and the code dv → moon = dv. That leaves aw = gives, sh = reflects, bo = and. So moon = dv. Option 4 (gl) is sun and option 3 (sh) is reflects — both appear alongside moon in one sentence but not in both.
What is the code for 'light'? (SI 1 Jul 2023)
- 1gl
- 2sh
- 3pu
- 4aw
Show answer
Answer: 3 — pu
Compare the statements two at a time; the word they share must map to the code they share. - Statements 1 and 2 share the word light and the code pu → light = pu. - Statements 1 and 3 share the word sun and the code gl → sun = gl. - Statements 2 and 3 share the word moon and the code dv → moon = dv. That leaves aw = gives, sh = reflects, bo = and. So light = pu. Option 1 (gl) is sun and option 4 (aw) is gives — both sit in the first sentence with light, but only pu recurs in the second sentence, which is what fixes it.
What will be the code for 'board'? (SI 2 Jul 2023)
- 1sv
- 2od
- 3fu
- 4rg
Show answer
Answer: 4 — rg
The codes are not in word order, so work by what the statements share. - 'black' is in statements 1 and 2; their only common code is 'od', so black = od. - 'bean' is in statements 1 and 3; their only common code is 'sy', so bean = sy. - 'board' is in statements 2 and 3; their only common code is 'rg', so board = rg. What is left then follows: in 1, salad = xt; in 2, of = fu; in 3, pin = ao. So board = rg. Option 2 ('od') is black, option 3 ('fu') is of, and 'sv' in option 1 appears in no statement at all.
What will be the code for 'bean'? (SI 2 Jul 2023)
- 1sy
- 2ao
- 3xt
- 4od
Show answer
Answer: 1 — sy
The codes are not in word order, so work by what the statements share. - 'black' is in statements 1 and 2; their only common code is 'od', so black = od. - 'bean' is in statements 1 and 3; their only common code is 'sy', so bean = sy. - 'board' is in statements 2 and 3; their only common code is 'rg', so board = rg. What is left then follows: in 1, salad = xt; in 2, of = fu; in 3, pin = ao. So bean = sy. Option 4 ('od') is black, option 3 ('xt') is salad and option 2 ('ao') is pin — all three sit in the same statements as 'bean' but never in both of them.
Which of the following is the code for ‘cool’? (SI 3 Jul 2023)
- 1sip
- 2deh
- 3mun
- 4mem
Show answer
Answer: 2 — deh
Compare the sentences that share a word. 'Moon is cool' (deh mun ace) and 'Just be cool' (mem sip deh) have only the word 'cool' in common, and only the code 'deh' in common. So cool = deh. 'mun' is the trap: it is common to 'Sun is hot' and 'Moon is cool', which share the word 'is', so mun = is.
What does ‘tr’ stand for? (SI 9 Jul 2023)
- 1hate
- 2run
- 3cute
- 4let
Show answer
Answer: 1 — hate
Line up the three coded sentences. Sentence · Words · Code 1 · dogs, are, cute · ly, uo, pj 2 · cats, hate, dogs · ky, tr, uo 3 · let, cats, run · yt, ky, ew 'dogs' is common to sentences 1 and 2, and 'uo' is the only code common to them, so dogs = uo. 'cats' is common to sentences 2 and 3, and 'ky' is the only code common to them, so cats = ky. Sentence 2 now has only 'hate' left to name and only 'tr' left to give it, so tr = hate. 'run' and 'let' cannot be right because they never appear in sentence 2 at all.
What is the code for ‘cat’? (SI 9 Jul 2023)
- 1ly
- 2ew
- 3ky
- 4uo
Show answer
Answer: 3 — ky
Line up the three coded sentences. Sentence · Words · Code 1 · dogs, are, cute · ly, uo, pj 2 · cats, hate, dogs · ky, tr, uo 3 · let, cats, run · yt, ky, ew Sentences 2 and 3 share exactly one word, 'cats', and exactly one code, 'ky', so cats (the stem's 'cat') = ky. 'uo' is the trap: it is the code shared by sentences 1 and 2, so it stands for 'dogs', not 'cats'.
Which of the following is the code for ‘there’? (SI 14 Jul 2023)
- 1has
- 2jok
- 3tum
- 4ftr
Show answer
Answer: 1 — has
Compare the statements two at a time and match the shared words with the shared codes. - Sentences 1 and 2 share only the word 'is', and they share only the code 'tum', so is = tum. - Sentences 1 and 3 share 'is' and 'angry', and they share 'tum' and 'ftr'; since is = tum, angry = ftr. - Sentences 2 and 3 share 'is' and 'girl', and they share 'tum' and 'jok'; since is = tum, girl = jok. - Sentence 3 is 'There is angry girl' = 'ftr tum jok has', and tum, ftr, jok are taken, so there = has. That also leaves bin = man in sentence 1 and nem = playing in sentence 2. So the code for 'there' is has. Option 4 (ftr) is the trap because ftr also appears in the third sentence, but ftr was already pinned to 'angry' by the overlap with the first sentence.
Which of the following is the code for ‘angry’? (SI 14 Jul 2023)
- 1jok
- 2has
- 3ftr
- 4tum
Show answer
Answer: 3 — ftr
Compare the statements two at a time and match the shared words with the shared codes. - Sentences 1 and 2 share only the word 'is', and they share only the code 'tum', so is = tum. - Sentences 1 and 3 share 'is' and 'angry', and they share 'tum' and 'ftr'; since is = tum, angry = ftr. - Sentences 2 and 3 share 'is' and 'girl', and they share 'tum' and 'jok'; since is = tum, girl = jok. - Sentence 3 is 'There is angry girl' = 'ftr tum jok has', and tum, ftr, jok are taken, so there = has. That also leaves bin = man in sentence 1 and nem = playing in sentence 2. So the code for 'angry' is ftr. Option 4 (tum) is the trap: tum is the code shared by all three sentences, and the word shared by all three is 'is', not 'angry'.
What is the code for 'long'? (SI 15 Jul 2023)
- 1wc
- 2gf
- 3sa
- 4ru
Show answer
Answer: 3 — sa
Compare the statements two at a time; the word they share must map to the code they share. - Lines 1 and 2 share only 'king', and share only the code 'ho' → king = ho. - Lines 1 and 3 share only 'queen', and share only the code 'gf' → queen = gf. - Lines 2 and 3 share only 'long', and share only the code 'sa' → long = sa. What is left is 'and' = sk, 'live' = ru and 'gown' = wc. So 'long' is coded as sa. Option 4 (ru) is the trap: ru appears in the same line as 'long', but ru is the leftover code for 'live', because 'live' occurs in that line only.
What is the code for 'queen'? (SI 15 Jul 2023)
- 1ho
- 2sk
- 3wc
- 4gf
Show answer
Answer: 4 — gf
Compare the statements two at a time; the word they share must map to the code they share. - Lines 1 and 2 share only 'king', and share only the code 'ho' → king = ho. - Lines 1 and 3 share only 'queen', and share only the code 'gf' → queen = gf. - Lines 2 and 3 share only 'long', and share only the code 'sa' → long = sa. What is left is 'and' = sk, 'live' = ru and 'gown' = wc. So 'queen' is coded as gf. Option 1 (ho) is the trap: ho also sits in line 1, but ho is the code shared by lines 1 and 2, whose only common word is 'king'.
What will be the code for 'goat'? (SI 15 Jul 2023)
- 1zo
- 2cb
- 3hu
- 4ki
Show answer
Answer: 1 — zo
Compare the statements two at a time; the one word they share must carry the one code they share. Statements compared · Common word · Common code 1 and 2 · road · hu 1 and 3 · runner · ki 2 and 3 · goat · zo Statements 2 and 3 share only the word 'goat' and only the code 'zo', so goat = zo. (The leftovers then follow: cheese = cb, rocks = sf, won = ma.) 'cb' is the trap — it is the leftover code for 'cheese' in statement 2, not for 'goat'.
What will be the code for 'road'? (SI 15 Jul 2023)
- 1sf
- 2cb
- 3ki
- 4hu
Show answer
Answer: 4 — hu
Compare the statements two at a time; the word they share carries the code they share. Statements compared · Common word · Common code 1 and 2 · road · hu 1 and 3 · runner · ki 2 and 3 · goat · zo Statements 1 ('road runner rocks' = 'sf hu ki') and 2 ('goat cheese road' = 'hu cb zo') have only 'road' in common and only 'hu' in common, so road = hu. 'ki' is the trap — it is shared by statements 1 and 3 and therefore stands for 'runner'.
What is the code for ‘money’? (SI 29 Jul 2023)
- 1kp
- 2hl
- 3vw
- 4sw
Show answer
Answer: 1 — kp
Compare the statements pair by pair and look for the one word they share. Statements 1 and 2 share only the word ‘time’, and their codes share only ‘nx’, so nx = time. Statements 1 and 3 share only the word ‘money’, and their codes share only ‘kp’, so kp = money. What is left of statement 1 gives vw = is. So the code for ‘money’ is kp. hl and sw (options 2 and 4) are the other two codes in the third statement, and they must stand for ‘we’ and ‘need’ in some order; vw (option 3) belongs to ‘is’.
What does the code ‘nx’ stand for? (SI 29 Jul 2023)
- 1time
- 2waste
- 3don’t
- 4is
Show answer
Answer: 1 — time
Compare the statements pair by pair and look for the one word they share. Statements 1 and 2 share only the word ‘time’, and their codes share only ‘nx’, so nx = time. Statements 1 and 3 share only the word ‘money’, and their codes share only ‘kp’, so kp = money. What is left of statement 1 gives vw = is. So nx stands for ‘time’. ‘waste’ and ‘don’t’ (options 2 and 3) are coded by um and py in some order, and ‘is’ is vw, so none of them can be nx.
What is the code for ‘friends’? (SI 31 Jul 2023)
- 1sd
- 2ay
- 3fp
- 4dp
Show answer
Answer: 4 — dp
Compare the sentences two at a time and match the word they share with the code they share. Sentences 1 and 2 share only 'loyal' and only the code 'gh', so loyal = gh. Sentences 2 and 3 share only 'friends' and only the code 'dp', so friends = dp. Sentences 1 and 3 share only 'are' and only the code 'sd', so are = sd. What is left: dogs = nt, live = fp, amazing = ay. So ‘friends’ is coded ‘dp’. ‘sd’ (option 1) is 'are', which also appears in the third sentence, and that is why it tempts.
What does the code ‘sd’ stand for? (SI 31 Jul 2023)
- 1dogs
- 2are
- 3friends
- 4loyal
Show answer
Answer: 2 — are
Compare the sentences two at a time and match the word they share with the code they share. Sentences 1 and 2 share only 'loyal' and only the code 'gh', so loyal = gh. Sentences 2 and 3 share only 'friends' and only the code 'dp', so friends = dp. Sentences 1 and 3 share only 'are' and only the code 'sd', so are = sd. What is left: dogs = nt, live = fp, amazing = ay. So ‘sd’ stands for ‘are’. ‘dogs’ (option 1) also sits in the first sentence but appears in no other sentence, so it must take the code that appears in no other line, which is ‘nt’.
In a certain code, ‘ae bi cee’ is related to ‘Apple is blue’, ‘dik eff’ is related to ‘black orange’, ‘cee fut eff’ is related to ‘orange is flower’. What is ‘Black flower’ related to as per the same code? (SI 31 Jul 2023)
- 1eff cee
- 2eff fut
- 3dik eff
- 4fut dik
Show answer
Answer: 4 — fut dik
Compare sentences that share a word. Sentences 1 and 3 share only the English word 'is' and only the code word 'cee', so cee = is. Sentences 2 and 3 share only 'orange' and only 'eff', so eff = orange. Sentence 3 then leaves fut = flower, and sentence 2 leaves dik = black. 'Black flower' is therefore dik fut, printed in the key as 'fut dik' — order is not fixed in this code. Option 3 (dik eff) is 'black orange', the trap of reusing sentence 2 whole.
What is the code for ‘surreal’? (SI 31 Jul 2023)
- 1ao
- 2mu
- 3zt
- 4gh
Show answer
Answer: 2 — mu
Compare the sentences pair by pair. Sentences 1 and 2 share only 'beauty', and their codes share only 'gh', so beauty = gh. Sentences 1 and 3 share only 'surreal', and their codes share only 'mu', so surreal = mu. Sentences 2 and 3 share only 'beast', and their codes share only 'ep', so beast = ep. So the code for 'surreal' is mu. gh (option 4) is beauty, carried by the first two sentences, and zt (option 3) is the leftover code for 'her'.
What is the code for ‘beast’? (SI 31 Jul 2023)
- 1Ep
- 2gh
- 3mu
- 4fk
Show answer
Answer: 1 — Ep
Compare the sentences pair by pair. Sentences 1 and 2 share only 'beauty', and their codes share only 'gh', so beauty = gh. Sentences 1 and 3 share only 'surreal', and their codes share only 'mu', so surreal = mu. Sentences 2 and 3 share only 'beast', and their codes share only 'ep', so beast = ep. So the code for 'beast' is ep, printed on the sheet as 'Ep'. fk (option 4) is the leftover code for 'and' in the second sentence, and mu (option 3) is surreal.
One question substitutes arithmetic signs — × means ÷, + means −, and so on — and asks for the value of an expression. Rewrite the whole expression with the real signs first, on paper, and only then compute; swapping signs mentally while calculating is where the marks go. The other is a data-sufficiency question: it asks not for the code but for which statements are enough to find it, and the test is the same overlap test applied to each combination in turn.
Both, solved (2)Tap to open
If ÷ means ×, × means +, + means − and − means ÷, find the value of 16 × 3 + 5 − 2 ÷ 4. (SI 2016)
- 19
- 210
- 319
- 415
Show answer
Answer: 1 — 9
First rewrite the expression, replacing every printed sign by what the code says it means: × becomes +, + becomes −, − becomes ÷, and ÷ becomes ×. So 16 × 3 + 5 − 2 ÷ 4 becomes 16 + 3 − 5 ÷ 2 × 4. Now apply BODMAS to the new expression, taking division and multiplication left to right before addition and subtraction: 5 ÷ 2 = 2.5, then 2.5 × 4 = 10. The expression is now 16 + 3 − 10 = 9. Option 3 (19) is what you get by stopping at 16 + 3 and forgetting the rest; option 2 (10) is only the division-multiplication part; and doing the operations left to right without BODMAS would give 15, which is option 4.
The question below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give answer : In a certain code, 'ma, ne, pi, ze' means 'Some flower are rose'. Which code word means rose? I - zi, pa, na, ai means 'All fruits are apple'. II - ne, fe, gi, qi means 'No lotus is rose'. (SI 20 Aug 2021)
- 1If the data given in both statements I and II together are not sufficient to answer the question
- 2If the data in statement I alone are sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question
- 3If the data given in both statements, statement I alone and statement II alone are independently sufficient to answer the question
- 4If the data in statement II alone are sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question
Show answer
Answer: 4 — If the data in statement II alone are sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question
The method for coded-language sufficiency is to look for the word the two sentences share and then for the code word they share. Statement II: 'No lotus is rose' shares exactly one content word with 'Some flower are rose' — rose. Its code 'ne, fe, gi, qi' shares exactly one word with 'ma, ne, pi, ze' — ne. One common word matched to one common code word fixes it: ne means rose. Statement II alone is sufficient. Statement I: 'All fruits are apple' shares no content word with the original sentence, and its code 'zi, pa, na, ai' shares no code word either, so it tells us nothing about rose. Statement I alone is not sufficient. That is exactly option 4. Option 3 would require statement I to work on its own, which it does not; option 1 is ruled out because II does settle the question.
Part 3 · Number and symbol coding — 8 questions
Read the key, write the plain string, then apply the conditions
These eight print a small table — digits and symbols on one row, letters on the other — followed by one or two conditions: if the first element is a symbol and the last is a digit, both are coded as X; if a vowel is followed by a digit, the digit takes the vowel's code. The conditions are where every mark is won or lost. Work in two separate passes and never merge them. First write out the plain codes straight from the table, with no conditions at all. Then go back and test each condition against the string you have written. Applying conditions while you read the table is how a candidate ends up applying one that does not hold. The remaining few in this group simply turn letters into digits — positions multiplied by place value, or reduced to their digital root — and are ordinary letter coding in disguise.
Every other number and symbol question (7)Tap to open
In a certain code language, ‘9091’ is coded as ‘900727’. How will ‘1808’ be coded in the same language? (SI 18 Aug 2021)
- 17210063
- 2307210
- 3172036
- 41072056
Show answer
Answer: 4 — 1072056
Multiply the digits by 10, 9, 8 and 7 according to their position, then write the products one after another. Check on the given pair: 9 × 10 = 90, 0 × 9 = 0, 9 × 8 = 72, 1 × 7 = 7, and stringing them gives 90|0|72|7 = 900727 ✓. That also explains why the code is longer than the number — some products are two digits. Apply it to 1808: 1 × 10 = 10, 8 × 9 = 72, 0 × 8 = 0, 8 × 7 = 56, giving 10|72|0|56 = 1072056. Option 1 (7210063) is the same idea worked from right to left and is the trap.
If in a certain code language, '46532' is coded as '59101011', then '7491' will be coded as : (SI 20 Aug 2021)
- 187148
- 256391
- 379159
- 495237
Show answer
Answer: 1 — 87148
The code is longer than the number because each digit becomes a number of its own and the results are written side by side. Split 59101011 as 5, 9, 10, 10, 11 against the digits 4, 6, 5, 3, 2 and look at what was added: 4 + 1 = 5, 6 + 3 = 9, 5 + 5 = 10, 3 + 7 = 10, 2 + 9 = 11. The amount added is 1 for the first digit and rises by 2 at each next place: 1, 3, 5, 7, 9. Apply the same to 7491, which has four digits and so uses 1, 3, 5, 7: 7 + 1 = 8, 4 + 3 = 7, 9 + 5 = 14, 1 + 7 = 8. Writing these side by side gives 8, 7, 14, 8 → 87148. Option 2 (56391) comes from adding 1 to every digit, and option 3 from adding 2 to each — both ignore that the increment itself grows.
In a certain code language, 'N' is written as '28' and 'POT' is written as '323040'. How will 'PET' be written in that code language? (SI 16 Oct 2022)
- 1321040
- 2312040
- 3302140
- 4302014
Show answer
Answer: 1 — 321040
Start from the single letter. N is the 14th letter and its code is 28 = 14 x 2. So each letter is coded as twice its alphabet position, written as a two-digit block. Check it on POT: Letter · Position · x 2 · Block P · 16 · 32 · 32 O · 15 · 30 · 30 T · 20 · 40 · 40 Strung together: 32 30 40 = 323040 ✓ exactly the code given. Now PET: Letter · Position · x 2 · Block P · 16 · 32 · 32 E · 5 · 10 · 10 T · 20 · 40 · 40 32 10 40 = 321040. The trap is E: 5 x 2 = 10, which must be written as the two-digit block "10", not as a single "1" or "0". Options 2, 3 and 4 all shuffle those digits (312040, 302140, 302014) and break the two-digit grouping.
A group of numbers and symbols is coded using letter-codes according to the codes given below and the conditions that follow them. Study the given codes and conditions and answer the question below. What will be the code for the following group? % 8 6 # 7 (SI 21 Jun 2023)
- 1Q F @ K Q
- 2Q @ @ K Z
- 3Q F E K Z
- 4Z E F K Q
Show answer
Answer: 2 — Q @ @ K Z
First write the plain codes from the table for % 8 6 # 7: % = Q, 8 = F, 6 = E, # = K, 7 = Z, giving Q F E K Z. Now test the conditions in order. (i) The second and third elements are 8 and 6; both are greater than 5, so both are replaced by @ → Q @ @ K Z. (ii) The first element is %, a symbol, not a number, so this condition does not apply. (iii) The first element % is a symbol but the last element 7 is a number, so this condition does not apply either. The final code is Q @ @ K Z. Option 3 (Q F E K Z) is the trap — it is the raw table code with no condition applied.
In a certain code language, 'CRISP' is written as '39917', and 'SOUP' is written as '1637'. How will 'RATING' be written in that language? (SI 2 Jul 2023)
- 1912957
- 2911957
- 3912867
- 4912857
Show answer
Answer: 1 — 912957
Each letter is replaced by the digit sum (digital root) of its alphabet position. CRISP: C=3→3, R=18→1+8=9, I=9→9, S=19→1+9=10→1, P=16→1+6=7, giving 39917. ✓ SOUP: S=19→1, O=15→6, U=21→3, P=16→7, giving 1637. ✓ RATING: R=18→9, A=1→1, T=20→2, I=9→9, N=14→5, G=7→7 → 912957. The distractors each spoil one letter — 911957 mis-codes T as 1, 912867 mis-codes I as 8, 912857 mis-codes both I and N.
In a certain code, (a) 'Ram better go' is written as '260', (b) 'better is here' is written as '278', (c) 'Ram is here' is written as '678', (d) 'better Ram here' is written as '267', (e) 'is and go' is written as '480'. Which of the following is the minimum set of statements needed to work out how 'better' is written in that code? (SI 14 Jul 2023)
- 1(a) and (d)
- 2(b), (e) and (d)
- 3(a) and (b)
- 4(b) and (d)
Show answer
Answer: 3 — (a) and (b)
Each statement gives a set of three words and a set of three digits, with no order. To pin down 'better' you need two statements whose only shared word is 'better' — then their only shared digit must be its code. Take (a) and (b): the words are {Ram, better, go} and {better, is, here}; the only common word is 'better'. The digits are {2, 6, 0} and {2, 7, 8}; the only common digit is 2. So better = 2, settled with two statements. Why the others fail: Option 1, (a) and (d): the words {Ram, better, go} and {better, Ram, here} share two words, 'Ram' and 'better', and the digits share 2 and 6 — you cannot tell which is which. Option 4, (b) and (d): they share 'better' and 'here', and the digits share 2 and 7 — again ambiguous. Option 2 uses three statements, so even if it worked it would not be the minimum set.
What will be the code for the following group? 7 # $ 3 6 (SI 31 Jul 2023)
- 1L T K P C
- 2C T T P L
- 3C K K P L
- 4© T K © L
Show answer
Answer: 2 — C T T P L
Read the plain codes first: 7 = C, # = T, $ = K, 3 = P, 6 = L, giving C T K P L. Now test the conditions. (i) The first element 7 is a number, but the last element 6 is not a perfect square, so no interchange. (ii) The second element (#) and the third element ($) are both symbols, so the third is coded with the second's code — K becomes T. (iii) The first element is a number, not a symbol, so © is not used. The group codes as C T T P L. Option 3 applies condition (ii) backwards and copies the third element's code onto the second.
Part 4 · The exam-hall routine
Three questions to ask, in this order
- Matching coded sentences word by word. The codes are never in the order of the English words. Use overlaps, not positions.
- Reading one shift and assuming it for the whole word. Twelve SI questions use position-wise shifts and the first letter is usually the one that looks simplest.
- Applying a condition while reading the key. Write the unconditional string first, then test the conditions on it. Two passes, never one.
- Forgetting that the second question uses the same sentences. Build the dictionary once and look down at question 44 before you turn the page.
- Decoding when the question asks you to code, or the reverse. Read the direction twice; both directions appear, and the trap option is the answer to the other one.
- Write the code under the word before thinking.
- Same letters, new order → rearrangement.
- Describe a rearrangement in position numbers.
- Opposite letter: 27 − position.
- A = 26 means the alphabet is numbered backwards.
- Short numeric code → a sum. Long one → letter by letter.
- Coded sentences: one shared word, one shared code.
- Two words shared → skip that pair, it proves nothing.
- Symbol tables: plain codes first, conditions second.
- Questions 43 and 44 share one set. Solve it once.