Aptitude Questions on Ratio-Proportion

  1. The 1st 3 terms of a proportion are 3, 9 and 12. The 4th term is:
    A. 18
    B. 24
    C. 30
    D. 36
  2. D. 36
    (9*12)/3 = 36
  3. A store owner is packing small radios into larger boxes that measure 25 * 42 * 60 inches. If the measurement of each radio is 7 * 6 * 5 inches, then how many radios can be placed in the box?
    A. 260
    B. 300
    C. 340
    D. 380
  4. B. 300
    Total no's of radios can be placed in the box (25 * 42 * 60) / (7 *6 * 5) = 6300 / 210 = 300
  5. 6 years ago, the ratio of the ages of Kunal and Sagar was 6:5. 4 years hence, the ratio of their ages will be 11:10. What is Sagar's age at present?
    A. 12 years
    B. 14 years
    C. 16 years
    D. 18 years
  6. C. 16 years
    Let the ages of Kunal and sagar be x and y respectively.
    According to the equation, (x-6)/(y-6) = 6/5
    => (x+4)/(y+4) = 11/10
    After solving we get y = 16
  7. If 40% of a number is equal to 2/3rd of another number, what is the ratio of 1st number to the 2nd number?
    A. 2 : 5
    B. 3 : 7
    C. 5 : 3
    D. 7 : 3
  8. C. 5 : 3
    Let 40% of A = 2/3 B. Then,
    40A/100 = 2B/3 => 2A/5 = 2B/3
    A/B = (2/3 * 5/2) = 5/3
    Hence, A : B = 5 : 3
  9. A gardener wants to plant trees in his garden in rows in such a way that the number of trees in each row to be the same. If there are 24 rows the number of trees in each row is 42. If there are 12 more rows find the number of trees in each row?
    A. 24 trees
    B. 28 trees
    C. 32 trees
    D. 36 trees
  10. B. 28 trees
    Required number of trees = 24/36 * 42 = 28
  11. The inverse ratio of 3 : 2 : 1 is?
    A. 1 : 2 : 3
    B. 2 : 3 : 1
    C. 3 : 1 : 2
    D. 2 : 3 : 6
  12. D. 2 : 3 : 6
    1/3 : 1/2 : 1/1 = 2 : 3 : 6
  13. If a:b = 4:1, then find (a - 3b) / (2a - b)?
    A. 1/7
    B. 2/7
    C. 3/7
    D. 5/7
  14. A. 1/7
    a/b = 4/1 => a = 4b
    (a - 3b) / (2a - b) = (4b - 3b) / (8b - b)
    = b/7b => 1/7
  15. The ratio of the incomes of Chetan and Dinesh is 3:4. The ratio of their expenditures is 5:7. If each of them saves Rs.200, find the incomes of both?
    A. Rs.600, Rs.800
    B. Rs.1200, Rs.1600
    C. Rs.1500, Rs.2000
    D. Rs.1800, Rs.2400
  16. B. Rs.1200, Rs.1600
    The savings of Chetan and Dinesh are 3x - 5y and 4x - 7y respectively.
    3x - 5y = 200 --- (1)
    4x - 7y = 200 --- (2)
    Multiplying (1) by 7 and (2) by 5 and subtracting the resultant equation (2) from resultant equation (1), we get x = 400.
    The incomes of Chetan and Dinesh are 3x = Rs.1200 and 4x = Rs.1600 respectively.
  17. A and B together have Rs. 1210. If 4/15 of A's amount is equal to 2/5 of B's amount, how much amount does B have?
    A. Rs. 460
    B. Rs. 484
    C. Rs. 550
    D. Rs. 664
  18. B. Rs. 484
    =>4/15 A = 2/5 B
    =>A = (2/5 * 15/4) B
    =>A = 3/2 B
    =>A/B = 3/2
    A : B = 3 : 2
    Therefore B's share = Rs. (1210 * 2/5) = Rs. 484
  19. Two numbers are respectively 20% and 50% more than a third number. The ratio of the two numbers is:
    A. 2 : 5
    B. 3 : 5
    C. 4 : 5
    D. 6 : 7
  20. C. 4 : 5
    Let the third number be x
    Then, first number = 120% of x = 120x/100 = 6x/5
    Second number = 150% of x = 150x/100 = 3x/2
    Ratio of first two numbers = 6x/5 : 3x/2 = 12x : 15x = 4 : 5