Aptitude Questions on Average

  1. A batsman in his 17th innings makes a score of 85 and their by increasing his average by 3. What is his average after the 17th innings?
    A. 34
    B. 35
    C. 36
    D. 37
  2. D. 37
    16x + 85 = 17(x + 3)
    x = 34 + 3 = 37
  3. The average of first 10 natural numbers is?

    A. 5
    B. 5.5
    C. 6
    D. 6.5
  4. B. 5.5
    Sum of 10 natural no. = 110/2 = 55
    Average = 55/10 = 5.5
  5. The average age of three boys is 15 years and their ages are in proportion 3:5:7. What is the age in years of the youngest boy?
    A. 9
    B. 12
    C. 15
    D. 18
  6. A. 9
    3x + 5x + 7x = 45
    x = 3
    3x = 9
  7. The average of 9 observations was 9, that of the 1st of 5 being 10 and that of the last 5 being 8. What was the 5th observation?
    A. 6
    B. 7
    C. 8
    D. 9
  8. D. 9
    1 to 9 = 9 * 9 = 81
    1 to 5 = 5 * 10 = 50
    5 to 9 = 5 * 8 = 40
    5th = 50 + 40 = 90 – 81 = 9
  9. A team of eight entered for a shooting competition. The best marks man scored 85 points. If he had scored 92 points, the average scores for. The team would have been 84. How many points altogether did the team score?
    A. 625
    B. 632
    C. 656
    D. 665
  10. D. 665
    8 * 84 = 672 – 7 = 665
  11. A batsman makes a score of 64 runs in the 16th innings and thus increased his average by 3. Find his average after the 16th inning?
    A. 17
    B. 18
    C. 19
    D. 20
  12. C. 19
    Let the average after the 16th inning be P.
    So, the average after the 15th inning will be (P-3)
    Hence, 15(P-30) + 64 = 16P => P = 19
  13. The average of 10 numbers is 23. If each number is increased by 4, what will the new average be?
    A. 23
    B. 25
    C. 27
    D. 29
  14. C. 27
    Sum of the 10 numbers = 230
    If each number is increased by 4, the total increase = 4 * 10 = 40
    The new sum = 230 + 40 = 270 The new average = 270/10 = 27
  15. Find the average of the series : 312, 162, 132, 142 and 122?
    A. 162
    B. 174
    C. 186
    D. 198
  16. B. 174
    (312 + 162 + 132 + 142 + 122)/5 = 870/5 = 174
  17. In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the run rate in the remaining 40 overs to reach the target of 282 runs?
    A. 5.75
    B. 6.25
    C. 6.75
    D. 7.25
  18. B. 6.25
    Required run rate = 282 - (3.2 * 10) / 40 = 250 / 40 = 6.25
  19. The average weight of 8 person's increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person?
    A. 75 kgs
    B. 80 kgs
    C. 85 kgs
    D. Data inadequate
  20. C. 85 kgs
    Total weight increased = (8 * 2.5) kg = 20 kgs
    Weight of new person = (65 + 20) kg = 85 kgs