Data Interpretation is the single largest topic in the Punjab Police SI's Quantitative Aptitude section — 109 questions since 2016, more than Mensuration and Number System put together. It is also the one where the arithmetic is easiest and the marks are lost anyway. Nothing here is harder than a percentage or an average. What the Commission actually tests is whether you can read the right cell. Almost every wrong option in this chapter is a correct calculation performed on the wrong row, the wrong year, or the wrong base. The 109 split into four shapes: 45 tables, 45 pie charts, 17 bar and line graphs and 2 caselets. Each has its own reading drill, and once you have the drill the sums take seconds.
The four reading drills
Learn these before you touch a single question.
Before you look at the chart at all, find out exactly what is being asked: which rows, which years, and whether the answer is a count, a ratio, a percentage or a difference. In this chapter the data is never the hard part. Every single wrong option is a sum that is correct for a question nobody asked — the 2010 total when both years were wanted, the female count when the male count was wanted, the later year as the base when the earlier one was. Knowing the target before you read the chart is what keeps you out of them.
When two quantities are shares of the same total, their ratio is the ratio of their percentages, and the total never enters the calculation. “Football 30%, badminton 10%, total 3,000 students — find the ratio” is just 30 : 10 = 3 : 1. You never need the 3,000. The same holds for differences expressed as a share: if one slice is 43% and another 23%, the gap is 20% of the total, which is one multiplication instead of three.
Tables
Forty-five questions. Build the totals once.
The set below carried ten questions in the 16 October 2022 paper — the longest single data set the SI has ever used. Work out the five row totals and the five column totals before you read question one, and all ten become lookups.
| Sport | VIII | IX | X | XI | XII | Total |
|---|---|---|---|---|---|---|
| Swimming | 8 | 15 | 14 | 19 | 14 | 70 |
| Cricket | 12 | 15 | 11 | 19 | 18 | 75 |
| Lawn Tennis | 13 | 11 | 8 | 7 | 16 | 55 |
| Badminton | 20 | 10 | 7 | 6 | 9 | 52 |
| Football | 12 | 10 | 16 | 16 | 10 | 64 |
| Total | 65 | 61 | 56 | 67 | 67 | 316 |
Five more tables, each with four questionsTap to open
Debate, quiz and games across five colleges — 2 July 2023. Quiz row: P 31, Q 13, R 21, S 19, T 26. Debate row: R 18, Q 24, S 15.
What is the average number of students taking part in the quiz? (SI 2 Jul 2023)
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Read the Quiz row across all five colleges: 31 + 13 + 21 + 19 + 26 = 110. Average = 110/5 = 22. The Games row averages 23.4, which is why option B is offered.
How many students of college R are taking part in debate and quiz? (SI 2 Jul 2023)
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In column R, Debate = 18 and Quiz = 21, so the total is 39. Column Q would give 24 + 13 = 37 and column S 15 + 19 = 34 — the only real risk is picking the wrong column.
Campus placements by department, 2020 and 2021. 2020 boys 150, 120, 100, 200; girls 130, 140, 80, 150. 2021 boys 100, 100, 150, 100; girls 80, 100, 140, 120.
What is the difference between the total number of boys and total number of girls who got campus placement from all the departments in the year 2020? (SI 2 Jul 2023)
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Take the 2020 row only. Boys: 150 + 120 + 100 + 200 = 570. Girls: 130 + 140 + 80 + 150 = 500. Difference = 570 − 500 = 70. Chemistry runs the other way (120 boys against 140 girls), so every column has to be carried with its sign rather than assumed positive.
In the year 2021, the total number of girls who got campus placement from all the departments is approximately what percentage of the total number of boys who got campus placement? (SI 2 Jul 2023)
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Take the 2021 row only. Girls: 80 + 100 + 140 + 120 = 440. Boys: 100 + 100 + 150 + 100 = 450. Required percentage = (440/450) × 100 = 97.77…, about 97.7 per cent. Reversing the two gives 102.3 per cent, which is not on offer — a useful sign that you have the ratio the right way up.
Course enrolments, new and left, 2011–2013. New in 2013: Medical 169, Non-Medical 540, Arts 340, Commerce 230, Vocational 192. Arts: new 680 (2011), 256 (2012), 340 (2013); left 140 (2012), 110 (2013).
For which course there is maximum enrolment of new students in 2013? (SI 9 Jul 2023)
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Read the 2013 row, taking only the “New” column of each course: Medical 169, Non-Medical 540, Arts 340, Commerce 230, Vocational 192. Non-Medical leads at 540, comfortably ahead of Arts at 340. The “Left” columns are a distraction — the question asks only about fresh enrolment.
How many students are studying the Arts course in the year 2013? (SI 9 Jul 2023)
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Students still studying = everyone enrolled up to that year minus everyone who has left. Arts enrolled: 680 + 256 + 340 = 1,276. Arts left: 140 + 110 = 250. Still studying = 1,276 − 250 = 1026. The three wrong options are the loose parts of that same sum: 1,276 forgets the subtraction, 250 is only those who left, and 340 is just the 2013 intake.
Car sales by type, 2001–2007, in thousands. Sedan 76, 91, 95, 100, 90, 100, 130. Luxury 143, 125, 115, 95, 75, 60, 100. SUV 115, 100, 76, 140, 135, 170, 130. Minivan 102, 86, 104, 100, 75, 45, 100. Truck 107, 124, 130, 75, 90, 120, 140.
Which type of car has maximum total sales over all the years? (SI 14 Jul 2023)
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Add each column over the seven years: Sedan 682, Luxury 713, SUV 866, Minivan 612, Truck 786. SUV is the largest. Luxury is the trap because it starts highest in 2001 at 143 — but it falls every year while SUV climbs.
Sales of which type of car declined continuously from 2001 to 2006? (SI 14 Jul 2023)
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Walk down each column from 2001 to 2006 and check that every step is a fall. Luxury: 143, 125, 115, 95, 75, 60 — down at every step. Minivan: 102, 86, 104 — rises in 2003, so it is out. Truck and Sedan both rise at the first step. Minivan is the tempting answer because it ends far below where it started, but “continuously” requires every single year to be lower than the one before.
For which type of car there is a continuous decrease in sales from 2001 to 2006? (SI 29 Jul 2023)
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The same car-sales table, asked the other way round. Luxury runs 143, 125, 115, 95, 75, 60 — a fall at every step, so Luxury is again the answer. Truck rises at the first step, Sedan rises at the first step, and Minivan rises in 2003.
Which type of car has maximum total sales over all the years? (SI 29 Jul 2023)
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Column totals again: SUV 866, Truck 786, Luxury 713, Sedan 682 (Minivan, not offered, is 612). SUV is the largest.
What is the difference between the sales of luxury cars (in thousands) in the year 2003 and the year 2006? (SI 21 Jun 2023)
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From the same car table, read the Luxury column: 2003 = 115 and 2006 = 60. Difference = 115 − 60 = 55 thousand. Option A (60) is the 2006 figure itself and option B (75) is the 2005 figure — both read straight from the wrong cell.
By what percentage have the sales of minivans increased/decreased in the year 2007 as compared to the year 2003? (SI 21 Jun 2023)
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Minivan sales were 104 thousand in 2003 and 100 thousand in 2007 — a fall of 4. Percentage change is taken on the base year: 4/104 × 100 = 3.846%, which the paper prints as 3.84% (truncated rather than rounded). Dividing by the 2007 figure gives exactly 4%, which is where option B comes from.
Tables: manufacturing, schools and vacanciesTap to open
What is the difference between the number of manufacturing units of computers and the number of manufacturing units of watches in 2017? (SI 20 Jun 2023)
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Read the 2017 column: computers 825, watches 445. Difference = 825 − 445 = 380. Option A (540) comes from pairing 825 with the 2016 watch figure of 358.
What is the approximate percentage increase in the manufacturing units of TVs from the year 2018 to 2019? (SI 20 Jun 2023)
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TVs: 2018 = 799 and 2019 = 824, so the increase is 25. Percentage increase = (25/799) × 100 = 3.129…, about 3.13%. The base is always the earlier year.
School admissions and departures, 2015–2019. School B admissions 190, 165, 129, 184, 157 against departures 152, 109, 101, 111, 129. School C admissions: 140 in 2016, 151 in 2017.
In which year is the difference between the number of students who got admission in school B and the number of students who took a T.C. or passed out from the school B is maximum? (SI 15 Jul 2023)
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Subtract departures from admissions, year by year, in row B: 2015: 190 − 152 = 38 · 2016: 165 − 109 = 56 · 2017: 129 − 101 = 28 · 2018: 184 − 111 = 73 · 2019: 157 − 129 = 28. The largest gap is 73, in 2018. 2019 looks big only because its admission figure is large — its outflow is large too.
What is the percentage increase in the number of students who got admission in C from 2016 to 2017? (SI 15 Jul 2023)
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School C: 140 in 2016 and 151 in 2017, an increase of 11. Percentage increase = (11/140) × 100 = 7.86%. Using 151 as the base gives 7.28%, which is what makes 7.52% look plausible.
12th board results, four schools, 2012–2016 (appeared − passed = failed). Failures by school and year — A: 2, 5, 2, 2, 1. B: 4, 3, 3, 2, 2. C: 1, 3, 2, 2, 3. D: 2, 5, 8, 4, 4.
In which year was the total number of students that failed in the 12th board examination from all the four schools the lowest? (SI 29 Jul 2023)
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Failures = appeared − passed. Add each year's column: 2012: 2 + 4 + 1 + 2 = 9 · 2013: 16 · 2014: 15 · 2015: 10 · 2016: 10. The smallest total is 9, in 2012. 2015 and 2016 tie at 10, just one above, which is why both are offered.
From which school is the total number of students that failed in 12th board examination during 2012 to 2016 the highest? (SI 29 Jul 2023)
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Add each school's failures across the five years: A 12, B 14, C 11, D 23. D is highest, chiefly because of 2014, where 83 appeared and only 75 passed — eight failures in one year, more than school C managed in all five.
Government vacancies, 2016-17 and 2020-21. Lower division clerk 1000 → 1240. Patwar 2019-20: 700; 2020-21: 850.
What is the percentage increase in the number of vacancies for the post of Lower division clerk from 2016-17 to 2020-21? (SI 31 Jul 2023)
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Vacancies go from 1,000 to 1,240, an increase of 240. Percentage increase = (240/1000) × 100 = 24%. Dividing by 1,240 gives 19.4%, which is where option A's 20% comes from.
If reservation for the O.B.C. category for the post of Patwar in 2020-21 is 18%, then what is the number of vacancies for the post of Patwar reserved for the O.B.C. category? (SI 31 Jul 2023)
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The Patwar row for 2020-21 shows 850 vacancies, and 18% of 850 = 153 — a whole number, so no rounding is needed. Using the 2019-20 figure of 700 would give 126, so the right row and the right year both matter.
Showroom sales, 2010–2014. Washing machines 105, 144, 156, 190, 205. Refrigerators: 256 in 2012, 279 in 2013, 226 in 2014. ACs: 219 in 2012, 179 in 2013.
What was the average number of washing machines sold by the showroom from the year 2010 to 2014? (SI 31 Jul 2023)
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Add the washing-machine column: 105 + 144 + 156 + 190 + 205 = 800. Average over five years = 160. The sum is exact, so no rounding is involved — the other options come from dropping or misreading one entry.
What was the increase in the sale of refrigerators in the showroom from the year 2012 to 2013? (SI 31 Jul 2023)
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The refrigerator column shows 256 in 2012 and 279 in 2013, so the increase is 23. Reading the AC column instead (219 to 179) gives a fall of 40, and reading 2013 to 2014 (279 to 226) gives a fall of 53 — the column and the year pair both have to be right.
Tables: marks, employees and single-question setsTap to open
What is the average percentage of marks that Chavi scored? (SI 31 Jul 2023)
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Chavi's row is 85, 79, 87, 75, 84, which sums to 410. Average = 410/5 = 82%. Option B (85%) is her best single class.
If in class VII, the total marks of all subjects are 600, then how many marks were scored by Mohan? (SI 31 Jul 2023)
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Mohan's entry in the class VII column is 70, i.e. 70%. Marks = 70% of 600 = 420. Option B (480) is 80% of 600, which is the wrong row.
What are the average marks of the students in History? (SI 31 Jul 2023)
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The History column reads 110, 125, 140, 110, 90, 85, which sums to 660. There are six students, so the average is 660/6 = 110. Dividing by five gives 132 and pulls you towards 140.
How many students obtained 70% and above in Arts? (SI 31 Jul 2023)
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Arts is marked out of 80, so 70% means 0.70 × 80 = 56 marks. Arts marks: Joseph 35, Kriti 60, Maina 40, Supreet 45, Jai 60, Dev 50. Only Kriti and Jai reach 56, so the answer is 2 students. Treating the marks as percentages directly would wrongly admit Dev and Supreet.
The production of mobiles by company B is approximately what percentage more than the production of mobiles by company D? (SI 29 Jun 2023)
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Mobiles: company B = 255 and company D = 175, both in hundreds, so the units cancel. Percentage more = (255 − 175)/175 × 100 = 80/175 × 100 = 45.71%, about 46%. The base must be D, the company being compared against. Using B gives 31.4%.
Which of the following companies produced the maximum number of electronic gadgets? (SI 29 Jun 2023)
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Add each company's row across all five gadgets (in hundreds): A = 855 · B = 675 · C = 505 · D = 495 · E = 870. E is the largest, just ahead of A. A is the trap: it leads on TVs, but E leads on mobiles, refrigerators, smart watches and washing machines.
The given table represents the number of students studying different subjects in Seth Dayal Singh College. Study the table and answer the question that follows. What is the average number of female students in all the subjects in the college? (SI 18 Aug 2021)
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Read only the Female row: 45 + 54 + 25 + 89 + 82 = 295 over five subjects. Average = 295/5 = 59. For contrast the Male row averages (53 + 62 + 85 + 55 + 50)/5 = 61, so none of the wrong options is the male figure either.
Marks bands and student counts. 1–10: 5 students · 11–20: 1 · 21–30: 3 · 31–40: 4 · 41–50: 2. Fifteen students in all.
The following table shows the marks range and number of students scoring in that range. If every student scoring 10 or less is given a grace and moved to the next score range, what will be the new student count in the score range of 11 - 20? (SI 18 Aug 2021)
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“Scoring 10 or less” is exactly the 1–10 band, which holds 5 students. The 11–20 band already holds 1. After the grace the 11–20 band holds 1 + 5 = 6. Option A (5) counts only those who moved and forgets the student already there.
The following table shows the marks range and number of students scoring in that range. How many students scored 40 or less? (SI 18 Aug 2021)
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“40 or less” covers the first four bands: 5 + 1 + 3 + 4 = 13. Sensible check by subtraction: the whole table holds 15 students and the 41–50 band holds 2, so 15 − 2 = 13.
Calculate the number of students passing the exam, considering a score of 30 or less as fail. (SI 18 Aug 2021)
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A score of 30 or less fails, so the failing bands are 1–10, 11–20 and 21–30, holding 5 + 1 + 3 = 9 students. The passing bands are 31–40 and 41–50, holding 4 + 2 = 6. (Total 15: nine fail, six pass.)
If the ratio of the number of males to females in town R is 2 : 3, then what is the average age of males and females together in town R? (SI 18 Aug 2021)
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Town R has an average male age of 30 and an average female age of 25, with males : females = 2 : 3. Take 2 men and 3 women: total age = 2 × 30 + 3 × 25 = 60 + 75 = 135 over 5 people, so the combined average is 135/5 = 27 years. This is a weighted average, not a midpoint — the plain midpoint 27.5 would ignore that the larger group is the younger one.
The number of mimicry shows held in city M is what percent of the number of drama shows held in city O? (SI 18 Aug 2021)
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Mimicry shows in city M = 0.9 hundreds and drama shows in city O = 12 hundreds. Both are in the same unit, so the hundreds cancel. Required percentage = (0.9/12) × 100 = 90/12 = 7.5. Rounding 0.9 up to 1 gives 8.33, which is where option B comes from.
Study the given table and answer the question that follows it. If the number of TUVs in 2020 is likely to increase over 2019 by the same percentage as it increased in 2019 over 2018, about how many TUVs will be sold in 2020? (SI 19 Aug 2021)
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Only the TUV column is needed: 48.25 lakh in 2018 and 67.25 lakh in 2019. The 2019 growth was (67.25 − 48.25)/48.25 ≈ 39.38 per cent. Applying the same rate to 2019 gives 67.25 × 67.25/48.25 ≈ 93.73 lakh. The neat way to see it: 2020/2019 = 2019/2018, so the three figures form a geometric step. Option C (87.36) is what you get by adding the same absolute rise of 19 lakh.
Which of the following newspapers have equal sales? (SI 19 Aug 2021)
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Read the sales column: newspaper 1 = 3, 2 = 2, 3 = 3, 4 = 3, 5 = 5, 6 = 4 lakh. Test each option: 2 and 4 are 2 and 3 — no. 3 and 6 are 3 and 4 — no. 5 and 6 are 5 and 4 — no. 1, 3 and 4 are all 3 lakh — equal.
If newspapers ______ and ______ are merged together, then their total sales will match the total sales of newspaper ______. (SI 19 Aug 2021)
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Add the first two newspapers in each option and see whether the sum matches the third. The figures are 1 = 3, 2 = 2, 3 = 3, 4 = 3, 5 = 5, 6 = 4 lakh. 1, 2, 5: 3 + 2 = 5, and newspaper 5 sells 5 lakh — a match. 1, 2, 6: 5 against 4 — no. 2, 5, 6: 7 against 4 — no. 2, 4, 6: 5 against 4 — no. The last is the near miss: it produces the right total but points it at the wrong paper.
The total expenditure on salary in 2016 was approximately what percent of the total expenditure on salary in 2019? (SI 20 Aug 2021)
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The Salary column shows 754 lakh in 2016 and 998 lakh in 2019. Required percentage = (754/998) × 100 ≈ 75.55%. Option D (132.36%) is the same comparison the wrong way round — the standard trap when the smaller figure is the one being expressed as a percentage.
Number of items rejected by unit C in year 2017 is what approximate percentage less than the number of items rejected by unit C in year 2013? (SI 20 Aug 2021)
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The table gives production and a rejection rate, so the rejected count is production × rate. Unit C, 2013: 56 thousand × 0.8% = 448 items. Unit C, 2017: 48 thousand × 0.2% = 96 items. Percentage less = (448 − 96)/448 × 100 = 78.57%, about 78%. Option C (21%) is the fall in production alone, ignoring the rate — the commonest error here. Options B and D exceed 100%, which is impossible for a decrease.
The table given below shows the number/percentage of male and female employees in five different companies. What is the difference between total male employees in company B and D together and total female employees in company A, C and E together? (SI 20 Aug 2021)
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Three of the four counts are printed directly. Male employees in B and D = 35 + 54 = 89. Female employees in A, C and E = 39 + 50 + 54 = 143. Difference = 143 − 89 = 54. The percentages are there to tempt a longer route, and they check out: in company A the men are 48 per cent, so the 39 women are 52 per cent and the staff is 75; in C the 50 women are 40 per cent, giving 125; in E the 54 women are 36 per cent, giving 150. Every derived total is a whole number, which confirms the reading.
Pie charts
Forty-five questions. Check the slices add up, then convert once.
Before anything else, add the printed labels. A percentage pie must total 100; a degree pie must total 360. If yours does not, you have misread a slice — and the paper's wrong options are built precisely on those misreadings. This takes four seconds and it has saved candidates more marks in DI than any formula on this page.
Pie charts where the slices alone give the answerTap to open
What is the ratio of students in football and badminton? (SI 3 Jul 2023)
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Both games are shares of the same total, so the ratio of students is the ratio of the percentages and the 3,000 is never needed. Football : Badminton = 30 : 10 = 3 : 1. (Check: 900 : 300 = 3 : 1.) Option C (1 : 3) is the same ratio the wrong way round.
What will be the ratio of the use of gold and platinum to the use of iron and silver? (SI 20 Jun 2023)
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Gold + platinum = 70% + 5% = 75%. Iron + silver = 15% + 10% = 25%. Ratio = 75 : 25 = 3 : 1. Because both groups are percentages of the same total, the weight of the ring never enters the calculation.
What is the ratio of the number of employed men to the number of employed women? (SI 21 Jun 2023)
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Employed men : employed women = 35 : 20 = 7 : 4 after dividing by 5. In absolute numbers it is the same: 28,000 : 16,000 = 7 : 4.
What is the ratio of maximum to minimum expenditure? (SI 14 Jul 2023)
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The five slices are Ration 40%, Other 25%, Study 20%, Electricity 10% and T.V. & Mobile 5%. Largest is Ration at 40%, smallest is T.V. & Mobile at 5%, so the ratio is 40 : 5 = 8 : 1. The income never needs to be known.
What is the ratio between the amount of funds raised from the Investors and the total amount of funds raised? (SI 20 Aug 2021)
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Total funds = 76,000 + 1,45,000 + 45,000 + 22,000 + 1,29,000 = ₹4,17,000. Investors : Total = 1,29,000 : 4,17,000 = 129 : 417, and both are divisible by 3, giving 43 : 139. Option B uses the bank-loan slice instead of the investors' slice and leaves it unreduced.
The given pie chart shows a person's expenditure under different heads as a percentage of his income. The average of the amounts spent on travelling and education is what percent more than the average of the amounts spent on food and house rent? (SI 19 Aug 2021)
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Every head is already a percentage of the same income, so the percentages can be treated as the amounts themselves. Average of travelling and education = (5 + 28)/2 = 16.5. Average of food and house rent = (15 + 12)/2 = 13.5. Excess = 3, taken as a percentage of the second average: 3/13.5 × 100 = 22.22 per cent. Option B (18.18) divides by the first average instead — “more than” always fixes the denominator on the quantity that follows those words.
Total exports of which of the following three companies is exactly half of the total export by all the six companies during 2021? (SI 16 Oct 2022)
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Half the pie is 50%. The shares are A 21, B 12, C 14, D 17, E 16, F 20, which add to 100. A + C + F = 55 · C + E + F = 50 ✓ · E + D + A = 54 · E + B + D = 45. Only C, E and F make exactly half.
What is the difference in the value of exports by D and E? (SI 16 Oct 2022)
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D has 17% and E has 16%, so the gap is just 1% of the total. 1% of ₹68 lakh = ₹68,000. The digits mislead candidates into ₹34,000, which would be half a percentage point.
What is the value of total exports during 2021 by A, C and E taken together? (SI 16 Oct 2022)
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A + C + E = 21 + 14 + 16 = 51% of the total. 51% of ₹68 lakh = 68 × 51/100 = ₹34.68 lakh. ₹36.75 lakh would need 54.04% — no sum of three shares reaches it.
What is the difference between the total value of exports by A and F together and the total value of export by C and D together? (SI 16 Oct 2022)
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A + F = 41% and C + D = 31%, so the difference is 10% of the total. 10% of ₹68 lakh = ₹6.8 lakh.
What is the value of exports by B during 2021? (SI 16 Oct 2022)
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B holds the smallest slice, 12%. 12% of ₹68 lakh = ₹8.16 lakh. Quick check: 1% is ₹0.68 lakh, so 12% = 12 × 0.68 = 8.16.
Pie charts: per cent of a given totalTap to open
What is the number of students enrolled in hockey? (SI 3 Jul 2023)
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Hockey takes 15% of the enrolment and the total is 3,000 students. Students in hockey = 15% of 3,000 = 450. Option A (350) would be under 12% and option C (550) over 18% — neither matches the printed slice.
If ₹12,000 was spent on sand, then how much money was spent on cement? (Assume that the amount spent is directly proportional to the consumption of material) (SI 3 Jul 2023)
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Sand is 15% of the material and cement is 20%, and spending is proportional to consumption. 15% ↔ ₹12,000, so 1% ↔ 12,000/15 = ₹800, and cement at 20% ↔ 20 × 800 = ₹16,000. As a ratio it is one step: cement/sand = 20/15 = 4/3, so 12,000 × 4/3 = ₹16,000.
If the weight of a ring is 10 g, then what will be the weight of the platinum used in making the ring? (SI 20 Jun 2023)
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The chart gives gold 70%, iron 15%, silver 10% and platinum 5%, which totals 100%. Platinum = 5% of 10 g = 0.5 g. Option B (1.0 g) is silver's 10% share, the slice next to platinum on the chart.
If monthly income of family is 50,000 then what is the expenditure of family on electricity? (SI 14 Jul 2023)
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Electricity is the 10% slice and the chart gives shares of total income. Electricity bill = 10% of ₹50,000 = ₹5,000. ₹3,000 would need a 6% slice and ₹4,200 an 8.4% slice; neither is on the chart.
How many unemployed men are there in the city? (SI 21 Jun 2023)
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Unemployed men are the 15% slice and the population is 80,000. Count = 15% of 80,000 = 12,000. Option A (15,000) is the mistake of reading the label 15 as thousands.
Orange production in Maharashtra is how many kg more than that in Karnataka? (SI 15 Jul 2023)
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Maharashtra is 25% and Karnataka 15%, so the gap is 10 percentage points. 10% of 3,000 kg = 300 kg. (The long way gives 750 − 450 = 300.)
How many kg of oranges is produced in Rajasthan and Punjab? (SI 15 Jul 2023)
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Rajasthan 20% and Punjab 30% together hold 50% of the crop. 50% of 3,000 kg = 1,500 kg.
How many more people prefer Rayon, Silk and Chiffon than the number of people who prefer Velvet, Wool and Denim? (SI 29 Jun 2023)
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Rayon + Silk + Chiffon = 14 + 12 + 17 = 43%. Velvet + Wool + Denim = 8 + 6 + 9 = 23%. Difference = 20% of 45,000 = 9,000. Take the percentage difference first; converting all six slices separately is what produces the 10,500 and 11,200 distractors.
How much has the girl spent on makeup accessories? (SI 15 Jul 2023)
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The five sectors are 110 + 86 + 72 + 64 + 28 = 360°, so the whole circle is the full ₹10,000. Makeup accessories take 72°, so the amount = (72/360) × 10,000 = ₹2,000. ₹2,500 is the trap for treating a 72° sector as a quarter of the circle.
With respect to the total expenditure, what percentage of the total amount has been spent by the girl on clothing, footwear and jewellery? (SI 15 Jul 2023)
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Clothing 110° + Footwear 86° + Artificial jewellery 64° = 260°. Percentage = (260/360) × 100 = 72.22%. 75% is the trap for rounding 260° up to 270°, which is exactly three quarters.
If the total area of the orchard is 500 acres, what will be the total area under orange and guava? (SI 1 Jul 2023)
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The five sectors are 100 + 90 + 80 + 60 + 30 = 360°, so the chart is complete. Orange 100° + Guava 80° = 180°, exactly half the circle, so the area is half of 500 = 250 acres. The three near-miss options exist only to punish eyeballing the sectors instead of adding the printed degrees.
If 30% of the pomegranate is replaced by apple, what will be the new total central angle formed by apple? (SI 1 Jul 2023)
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Pomegranate occupies 60°. Transferring 30% of it moves 0.30 × 60 = 18°. Apple was 30°, so the new apple angle = 30 + 18 = 48°. (Pomegranate drops to 42°, and the circle still totals 360°.) The trap is to take 30% of 100 rather than 30% of the 60° sector.
If 20% of the people who prefer Cotton switch to Georgette, then what will be the new percentage of people who prefer Georgette? (SI 29 Jun 2023)
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Cotton is 15% and Georgette 19% of the same total, so the shares add and subtract directly. 20% of the Cotton share = 0.20 × 15% = 3% of the total. New Georgette share = 19 + 3 = 22%. The total number of people does not change, so no re-basing is needed. Option D (39%) comes from adding 19% and 20% as if the 20% were of the whole.
If the total marks in Mathematics and History together are 450, then how many marks will be in English only? (SI 18 Aug 2021)
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Mathematics 14% and History 22% together are 36% of the total marks, and that 36% equals 450. So 1% = 450/36 = 12.5 marks (and the whole paper is 1,250 marks). English is 12%, so English marks = 12 × 12.5 = 150.
Pie charts with a two-step twistTap to open
Of the number of wallets sold, brands P, R and S sold 20%, 30% and 10% respectively to female customers. What is the total number of wallets of brands P, R and S sold to female customers? (SI 1 Jul 2023)
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Convert each share of the 400 wallets into a count first, then take the female percentage of each: P: 10% of 400 = 40, of which 20% = 8. R: 20% of 400 = 80, of which 30% = 24. S: 25% of 400 = 100, of which 10% = 10. Total = 8 + 24 + 10 = 42. The trap is to add the three female percentages (20 + 30 + 10 = 60) — they apply to different bases and cannot be added.
If the total number of boys present on Wednesday and Thursday was 98 and 105 respectively, how many students (boys + girls) were present on Wednesday and Thursday together? (SI 2 Jul 2023)
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The 360 girls split Monday 15%, Tuesday 10%, Wednesday 40%, Thursday 35%. Wednesday and Thursday together are 75% of 360 = 270 girls. Boys on the two days = 98 + 105 = 203. Total = 270 + 203 = 473. Adding the two shares first saves computing each day.
If the number of boys who attended the seminar from Delhi and Surat was 124 and 60, respectively, then what was the respective ratio between the number of attendees (boys + girls) from Delhi and Surat? (SI 3 Jul 2023)
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Girls from Delhi = 25% of 800 = 200, so Delhi's total = 200 + 124 = 324. Girls from Surat = 24% of 800 = 192, so Surat's total = 192 + 60 = 252. Ratio = 324 : 252; dividing both by 36 gives 9 : 7. Comparing only the girls gives 25 : 24, and forgetting one boy count gives 9 : 5.
If the manufacturing cost per table of Brand R and S was ₹500 and ₹800, respectively, what was the total manufacturing cost incurred by Brand R and S together? (in ₹) (SI 9 Jul 2023)
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Check the chart first: P 20%, Q 10%, R 40%, S 18%, T 12% add to 100%. R makes 40% of 500 = 200 tables at ₹500 each = ₹1,00,000. S makes 18% of 500 = 90 tables at ₹800 each = ₹72,000. Total = ₹1,72,000. Option A (₹1,84,000) swaps the two per-table costs.
If 70% of the TV sets of Type B are sold by the company, then how many TV sets are left unsold of type B? (SI 9 Jul 2023)
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Type B is 30% of 2,50,000 = 75,000 sets. 70% are sold, so 30% remain: 30% of 75,000 = 22,500. Note the two different 30%s — one is the share of production, the other the unsold fraction of that share.
If 75% of the T.V. of type D is sold then how many perfect T.V. are left unsold of type D? (SI 9 Jul 2023)
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Type D is 25% of 2,50,000 = 62,500 sets. 75% are sold, so 25% remain: 25% of 62,500 = 15,625. The word “perfect” in the printed stem adds nothing — no defect rate is given anywhere in the data.
Out of the number of tickets sold in May, 50% were sold to females. Out of the total number of tickets sold in July, 40% were sold to females. What is the difference between the number of tickets sold to males in May and July? (SI 29 Jul 2023)
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May = 12% of 550 = 66 tickets; July = 50% of 550 = 275 tickets. Males in May = 50% of 66 = 33. Males in July = 60% of 275 = 165. Difference = 165 − 33 = 132. Comparing the female counts instead gives 77.
The given pie chart depicts the number of tickets sold for five different cities, out of the total number of tickets sold (which is 1050) for the given five cities together. Study the chart and answer the question that follows. Out of the number of tickets sold for Srinagar, 121 were sold to females. Out of the total number of tickets sold for Kochi, 98 were sold to females. What is the difference between the number of tickets sold to males for Srinagar and Kochi? (SI 31 Jul 2023)
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Total tickets 1,050, so one per cent is 10.5 tickets. Srinagar 22% = 231 tickets, of which 121 female, so males = 110. Kochi 18% = 189 tickets, of which 98 female, so males = 91. Difference = 110 − 91 = 19. Each city total must be reduced by its own female count first.
Study the given pie-chart. Out of the total number of sweaters purchased of brands Q, R and S together, three-fourth were merino wool sweaters. What is the total number of merino wool sweaters purchased of brands Q, R and S? (SI 31 Jul 2023)
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Q, R and S together hold 35 + 20 + 15 = 70% of the purchases, which is 70% of 240 = 168 sweaters. Three-fourths of those are merino wool: (3/4) × 168 = 126. Leaving out brand S gives 55% of 240 = 132 (option D), and rounding 168 down to 160 gives 120 (option C).
Study the given pie chart and answer the given question. The total cost of producing brand Y's chairs was ₹56,000. If the cost of producing one chair of brand A was ₹100 less than that of brand Y, then what was the total cost of producing brand A's chairs? (SI 21 Jun 2023)
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Shares: A 36%, B 24%, X 12%, Y 28%, on a total of 400 chairs. Brand Y made 28% of 400 = 112 chairs costing ₹56,000 in all, so one Y chair costs 56,000/112 = ₹500. One A chair costs ₹100 less = ₹400. Brand A made 36% of 400 = 144 chairs, so the total is 144 × 400 = ₹57,600.
25 percent of the number of faculties in Medical department are females. What is the number of male faculty in the department? (SI 20 Aug 2021)
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Check the chart first: 15 + 19 + 11 + 16 + 27 + 12 = 100 per cent, so no slice is misread. Medical is 19% of 7,200 = 1,368 faculty. Of those 25% are women, so 75% are men: 1,368 × 0.75 = 1,026. The three wrong options are all within twenty of the right figure, which is exactly where a slipped digit lands — so both steps have to be exact.
If 100 more customers were surveyed, and 20% of them stated Dal Makhani as their favourite dish, what would be the new percentage of customers having Dal Makhani as the favourite dish? (SI 18 Aug 2021)
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First survey: Dal Makhani has 25% of 200 = 50 customers. Second survey: 20% of the extra 100 = 20 customers. New total = 70 out of a new sample of 300, so the share = (70/300) × 100 = 23.3%. The trap is to average the two percentages (giving 22.5%); you must recompute over the enlarged total.
Pie charts with an extra figure outside the chartTap to open
The number of orders placed in February was 96 more than the number of orders placed in November. What is the average number of orders placed in December, January and February? (SI 14 Jul 2023)
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The pie splits 900 orders as October 40%, January 30%, November 20%, December 10%. November = 180, December = 90, January = 270. February is not on the chart — it is given as 96 more than November, so February = 180 + 96 = 276. Average of December, January and February = (90 + 270 + 276)/3 = 636/3 = 212.
The given pie chart depicts the number of burgers cooked in five months, out of the total number of burgers cooked (which is 1500) in the given five months together. Study the chart and answer the question that follows. The number of burgers cooked in October was 60 more than the number of burgers cooked in June. What is the average number of burgers cooked in August, September and October? (SI 20 Jun 2023)
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The slices are May 20%, June 35%, July 10%, August 20%, September 15% of 1,500. August = 300 and September = 225. June = 525, and October is stated to be 60 more, so October = 585 — it is extra data, not a slice. Average = (300 + 225 + 585)/3 = 1,110/3 = 370.
If the average number of people who travelled by the bus on Wednesday, Friday and Saturday was 201, what is the number of people who travelled by bus on Saturday? (SI 29 Jun 2023)
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The five days in the chart share 700 people. Wednesday = 35% of 700 = 245 and Friday = 28% of 700 = 196. The average of Wednesday, Friday and Saturday is 201, so their total is 603. Saturday = 603 − 245 − 196 = 162. Saturday is not on the chart, which is why its figure has to be recovered from the average.
What is the difference between the average number of children who participated from schools D and E combined and the average number of children who participated from schools A and B combined? (SI 15 Jul 2023)
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The slices are A 20%, B 12%, C 28%, D 18%, E 22% of 900. D + E = 40% of 900 = 360, so their average is 180. A + B = 32% of 900 = 288, so their average is 144. Difference = 180 − 144 = 36. The difference of the totals would be 72, twice as big — read whether averages or totals are wanted.
What is the difference between the average number of laptops sold in 2001 and 2002 and the average number of laptops sold in 2003 and 2004? (SI 15 Jul 2023)
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Convert each share of 800 laptops: 2001 = 25% = 200, 2002 = 20% = 160, 2003 = 45% = 360, 2004 = 10% = 80. Average for 2001 and 2002 = 180. Average for 2003 and 2004 = 220. Difference = 40. Eighty would be the answer if the question asked for the difference of the totals.
Bar and line graphs
Seventeen questions. Read the printed labels, not the bar heights.
1. Use the data labels. Almost every SI graph prints the value on or above each bar. Eyeballing against gridlines is what turns 49 into 54 and loses the mark. 2. Check the unit on the axis against the unit in the options. A graph in thousands with options in plain numbers means a factor of 1,000 at the end — a whole question has turned on nothing else. 3. “More than” excludes equality. When a plotted ratio is exactly 1, imports equal exports; they are not more.
Bar and line graphs: the restTap to open
What is the ratio of the number of players taking part in cricket to the number of players taking part in kho-kho? (SI 15 Jul 2023)
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From the graph, cricket has 54 players and kho-kho has 72. Ratio = 54 : 72, and dividing both by 18 gives 3 : 4.
What is the difference between the number of players taking part in volleyball and the number taking part in basketball? (SI 15 Jul 2023)
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Volleyball has 82 players and basketball 49, so the difference is 33. Option B (28) comes from reading the basketball bar off the gridline as 54 instead of its printed 49 — exactly the error the data labels are there to prevent.
The bar graph below shows the number of male and female employees working in five organisations. What is the ratio of the number of male employees of organisations Q and S taken together to the number of female employees of organisations R and T taken together? (SI 19 Aug 2021)
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Male employees in Q and S = 360 + 390 = 750. Female employees in R and T = 210 + 240 = 450. Ratio = 750 : 450, and dividing by 150 gives 5 : 3. The ratio must be built from exactly the four bars the question names.
The sales of company T were approximately what percentage of the combined total sales of the six companies given? (SI 19 Aug 2021)
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Read the six data labels: P 42, Q 56, R 67, S 39, T 70, U 86, totalling 360. T's share = 70/360 × 100 = 19.44 per cent. Sanity check: one sixth of the total would be 16.67 per cent, and T is a little above the average bar, so just under 20 per cent is exactly what to expect.
In which subject did Ramya score the highest marks? (SI 19 Aug 2021)
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Follow Ramya's line across the five subjects: English 80, Hindi 78, Science 85, Mathematics 92, Social Science 76. Mathematics is the single peak of the plot, the only point past 90. Kajol's line (75, 85, 65, 90, 85) also peaks at Mathematics, so the answer is safe on either reading of the two identically drawn lines.
How many runs did the team score in the sixth over? (SI 19 Aug 2021)
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The vertical axis is marked every 2 runs from 0 to 16, and the six bars stand at 4, 15, 8, 7, 10 and 3. The sixth bar stops midway between the 2 and 4 gridlines, so it is 3 runs — the shortest bar on the chart. Option C (4) is the height of the first bar, and it is where the eye lands if the sixth bar is rounded up to the nearest marked gridline.
In how many of the given years were the imports more than the exports in the case of company B? (SI 18 Aug 2021)
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Imports exceed exports exactly when the plotted ratio is greater than 1. Company B's values are 1993: 0.5, 1994: 0.8, 1995: 0.6, 1996: 1, 1997: 1.2, 1998: 1.4, 1999: 0.8. Only 1997 and 1998 are above 1, so the answer is 2 years. The trap is 1996, where the ratio is exactly 1 — imports then equal exports, which is not “more than”. Counting it gives the wrong answer 3.
The bar graph below shows Sujit's total income over five years and the percentage of that income which came from business A. His total income comes from business A and business B (income in ₹ lakh). For the given period, the average income from business A is approximately what percent more than the average income from business B? (SI 19 Aug 2021)
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The blue bar is the year's total income and the red bar is the percentage of it earned from business A, so A = total × per cent and B is whatever is left. 2010: A = 24, B = 36 · 2011: A = 30, B = 20 · 2012: A = 35, B = 35 · 2013: A = 13.5, B = 31.5 · 2014: A = 52, B = 13. Totals: A = 154.5, B = 135.5. Since both are over the same five years, the excess can be taken on the totals: (154.5 − 135.5)/135.5 × 100 ≈ 14 per cent. The trap is to average the red bars themselves (40, 60, 50, 30, 80 → 52 per cent) and conclude “about 20 per cent more” — a percentage of a changing total cannot be averaged that way.
The given bar chart shows the number of vehicles (in thousands) on the road in a particular city during the years 2016–2019. Over the whole period from 2016 to 2019, which type(s) of vehicle saw the smallest increase (the percentage increase is to be worked out on the 2016 figures)? (SI 19 Aug 2021)
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Only 2016 and 2019 matter, because the question fixes 2016 as the base. Autorickshaws go from about 4.25 to 4.5 thousand, taxis from 2.3 to 2.75, buses from 2 to 5. As percentages of their own 2016 values: autorickshaws 0.25/4.25 ≈ 6%, taxis 0.45/2.3 ≈ 20%, buses 3/2 = 150%. The smallest is autorickshaws. A large base makes a small percentage out of a respectable absolute gain — that is the whole point of the question.
The ratio of the number of years, in which the price of the shares are above the average shares, to those in which the shares are below the average shares is? (SI 20 Aug 2021)
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First the average of the six bars: 1170 + 1465 + 975 + 800 + 1140 + 1230 = 6,780, and 6,780/6 = 1,130. Above 1,130: 1170, 1465, 1140, 1230 — four years. Below: 975, 800 — two years. Ratio = 4 : 2 = 2 : 1. The trap is to call 1,140 “about average” and drop it, which would give 3 : 2 — but 1,140 is genuinely greater than 1,130.
The sales have increased by nearly 13% from May to June in case of? (Round of up to two decimal place) (SI 20 Aug 2021)
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Work out the percentage increase colour by colour, using (June − May)/May × 100: Blue 34.01% · Green 79.45% · Orange 13.04% · Red 19.47% · Yellow 2.76%. Only Orange is near 13%. Yellow is the trap for anyone comparing raw gaps instead of percentages — its bars are the closest together, but a small gap on a small base is still only 2.76%.
The line graph shows the export (in crores) of three companies over years. For which of the following pairs of years the total export from three companies together are equal? (SI 20 Aug 2021)
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Add the three companies year by year, using the printed labels: 2014: 232 · 2015: 188 · 2016: 170 · 2017: 182 · 2018: 171 · 2019: 170. Only 2016 and 2019 share a total, 170 crore each. Note how close 2018 comes at 171 — that single crore is what makes the other options wrong, so the totals must be added rather than eyeballed.
The line graph shows the number of vehicles (in thousand) manufactured by two companies over years. Find the difference between the total production of the two companies in the given years? (SI 20 Aug 2021)
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Add each company's five yearly figures. Company X: 133 + 145 + 164 + 189 + 190 = 821 thousand. Company Y: 147 + 160 + 140 + 170 + 230 = 847 thousand. Difference = 26 thousand = 26,000 vehicles. The units matter: the graph is in thousands but the options are in plain vehicles.
The following chart shows the number of students who passed the CAT exam or CET exam or CA foundation exam or none of these exams in three different years. (Assume that there are no students who passed more than one exam.) What was the percentage of students who succeeded in any one of the exam in 2015? (Correct up to two decimal places) (SI 20 Aug 2021)
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Work only with the 2015 bars. Students who passed some exam = CAT 840 + CET 470 + CA Foundation 1,100 = 2,410. Students who passed none = 400. Since no student passed more than one exam, the total for 2015 is 2,410 + 400 = 2,810. Required percentage = 2,410/2,810 × 100 = 85.76%. The “assume no student passed more than one exam” sentence is there precisely to license adding the bars without double counting.
Caselets
Two questions. Most of the paragraph is padding.
A caselet gives you a dozen sentences about six people and then asks about one of them. Do not build the whole table. Underline the name in the question, scan for every sentence that mentions it, and solve only those. In the two SI caselets, the useful sentences were two and three respectively. Everything else was there to burn your clock.
- Reading the wrong row or the wrong year. Almost every wrong option in this chapter is a correct sum on the wrong cells, which is why they look so plausible.
- Dividing by the later value in a percentage change. The base is always the value you started from.
- Adding percentages that sit on different bases. 20% of P plus 30% of R is not 50% of anything.
- Giving the difference of the totals when the question asked for the difference of the averages — it is always exactly twice as large for a pair.
- Ignoring the unit. A graph in thousands against options in plain numbers costs a mark that the arithmetic had already earned.
- Counting a value that is exactly equal when the question says “more than”.
- 1% of a pie = 3.6°; degrees ÷ 3.6 = per cent
- Same total → ratio of counts = ratio of percentages
- % change = change ÷ earlier value × 100
- “A is x% more than B” divides by B
- Add the slices before you use them
- Build row and column totals once, then look up
- Check the axis unit against the option unit
- In a caselet, solve only the lines that name your letter
Last line, then labels, then arithmetic. Read what is being asked before you look at the chart; read the printed numbers rather than the picture; and only then calculate. The sums in this chapter are the easiest in the paper — the marks go to whoever reads most carefully, not to whoever calculates fastest.