DILR guide, section 10

DI with charts

Chart-based DI is careful reading plus the percentage arithmetic from your QA prep: copy each value you need into your notes once, then compute. Six of the fifteen CAT 2025 sets were DI-style, so treat these as core, not optional.

Worked set 11, easy. Attempt it in 15 minutes first.

Bar chart

Five companies: revenue in 2024 and 2025, and profit in 2025All values in ₹ crore. Original practice data.
  • Revenue 2024
  • Revenue 2025
  • Profit 2025
  1. Alpha
    120
    150
    18
  2. Beta
    200
    210
    42
  3. Gamma
    80
    100
    15
  4. Delta
    150
    135
    24
  5. Epsilon
    60
    90
    9
Show as a table
CompanyRevenue 2024Revenue 2025Profit 2025
Alpha12015018
Beta20021042
Gamma8010015
Delta15013524
Epsilon60909

Questions

  1. Which company had the highest profit margin (profit ÷ revenue) in 2025?
  2. (TITA) What was the highest percentage growth in revenue from 2024 to 2025?
  3. (TITA) What was the total 2025 profit of the five companies, in ₹ crore?
  4. In how many companies was the 2025 profit margin above 15%?
Show solution

Work out the two derived numbers every question needs, one line per company:

  • Profit margin in 2025: Alpha 18/150 = 12%, Beta 42/210 = 20%, Gamma 15/100 = 15%, Delta 24/135 ≈ 17.8%, Epsilon 9/90 = 10%.
  • Revenue growth: Alpha +25%, Beta +5%, Gamma +25%, Delta −10%, Epsilon +50%.

Answers. (1) Beta. (2) 50, Epsilon. (3) 108: 18 + 42 + 15 + 24 + 9. (4) 2, Beta and Delta; Gamma’s 15% is not above 15%.

Takeaway. “Above 15%” excludes exactly 15%; read the inequality in every DI question before counting.

5 minutes, timed

Practice on the same bar chart

Use the bar chart above.

Questions

  1. (TITA) By how many crore did Delta’s revenue fall from 2024 to 2025?
  2. Which company’s 2025 revenue was closest to the five-company average?
  3. (TITA) What was the combined revenue growth of the five companies, in percent to one decimal place?
Show answers

(1) 15. (2) Delta: the average is 685 ÷ 5 = 137. (3) 12.3: revenue rose from 610 to 685, and 75/610 ≈ 0.123.

Worked set 12, medium. Attempt it in 15 minutes first.

Scatter plot

Ten students: Test 1 score (across) against Test 2 score (up)Both tests are out of 50. Points above the dashed line improved in Test 2. Original practice data.
0010102020303040405050same scoreA: Test 1 20, Test 2 29A (20, 29)B: Test 1 35, Test 2 30B (35, 30)C: Test 1 40, Test 2 45C (40, 45)D: Test 1 25, Test 2 25D (25, 25)E: Test 1 30, Test 2 37E (30, 37)F: Test 1 45, Test 2 40F (45, 40)G: Test 1 15, Test 2 22G (15, 22)H: Test 1 36, Test 2 43H (36, 43)I: Test 1 28, Test 2 20I (28, 20)J: Test 1 42, Test 2 48J (42, 48)Test 1 score

Questions

  1. (TITA) How many students scored higher in Test 2 than in Test 1?
  2. Which student improved the most?
  3. (TITA) What was the highest combined score across both tests?
  4. (TITA) How many students scored at least 40 in both tests?
Show solution

The dashed line marks equal scores: points above it improved, points below it fell, and D sits on it. Improvements: A +9, E +7, G +7, H +7, J +6, C +5. Combined scores: J has 90, ahead of C and F at 85 each. At least 40 in both tests: C (40, 45), F (45, 40) and J (42, 48); H misses with 36 in Test 1.

Answers. (1) 6: A, C, E, G, H and J. (2) A. (3) 90. (4) 3.

Takeaway. On a scatter plot, picture the line y = x first; it turns “who improved” into “which points sit above the line”. CAT also draws lines such as y = 2x to ask about ratios.

5 minutes, timed

Practice on the same scatter plot

Use the scatter plot above.

Questions

  1. (TITA) What was the average Test 1 score of the ten students?
  2. (TITA) How many students’ scores fell from Test 1 to Test 2?
  3. (TITA) What was the largest fall?
Show answers

(1) 31.6: the Test 1 scores add to 316. (2) 3: B, F and I. (3) 8, by I (28 to 20).