Ratio and proportion bits part-1

  1. The ratio of two numbers is 9 : 5. If 9 is added to the greater number and 5 is subtracted from the smaller number, the greater number becomes thrice the smaller one. Find the numbers.
    A. 72, 40
    B. 18, 10
    C. 36, 20
    D. None of these

  2. Find the ratio of the diagonal of a square of side 30 cm, to its side.
    A. √2: 3
    B. √3: 4
    C. 1 : √2
    D. √2: 1

  3. 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

  4. Seats for Mathematics, Physics and Biology in a school are in the ratio 5 : 7 : 8. There is a proposal to increase these seats by 40%, 50% and 75% respectively. What will be the ratio of increased seats?
    A. 2 : 3 : 4
    B. 6 : 7 : 8
    C. 6 : 8 : 9
    D. None of these

  5. In a mixture 60 litres, the ratio of milk and water 2 : 1. If this ratio is to be 1 : 2, then the quantity of water to be further added is:
    A. 20 litres
    B. 30 litres
    C. 40 litres
    D. 60 litres

  6. The ratio of A’s salary to B’s was 4 : 5. A’s salary is increased by 10% and B’s by 20%, what is the ratio of their salaries now?
    A. 14:11
    B. 15:14
    C. 11:15
    D. None of these

  7. A and B are the two alloys of copper and brass prepared by mixing metals in the proportion of 7:2 and 7:11 respectively. If the equal quantities of two alloys are melted to form a third alloy called C, then the proportion of copper and brass in C will be,
    A. 5:9
    B. 5:7
    C. 7:5
    D. 9:5

  8. A mixture of milk and water are in the ratio of 5:1. By adding 5 liters of water, the ratio of the milk to water becomes 5:2. The quantity of milk in the mixture is:
    A. 16 litres
    B. 25 litres
    C. 24 litres
    D. 22.75 litres

  9. The ratio of the number of UG students and PG students in a college is 5:4. If 40% of the UG students and 50 % of the PG students are scholarship holders. What percentage of the students does not get the scholarship?
    A. 54.60%
    B. 55.20%
    C. 55.50%
    D. 54.30%

  10. One year ago the ratio between Lalitha’s and Ganga’s salary was 3 : 4. The ratios of their individual salaries between last year’s and this year’s salaries are 4 : 5 and 2 : 3 respectively. At present the total of their salary is Rs. 4160. The salary of Lalitha, now is
    A. Rs. 1040
    B. Rs. 1600
    C. Rs. 2560
    D. Rs. 3120

Correct Answers:

  1. C
  2. D
  3. C
  4. A
  5. D
  6. C
  7. C
  8. B
  9. C
  10. B