2018 · Q47
The ratio of the sum and difference of the ages of the father and the son is 11 : 3. Consider the following statements : 1. The ratio of their ages is 8 : 5. 2. The ratio of their ages after the son attains twice the present age will be 11: 8. Which ofthe statements given above is/are correct ?
Elementary MathematicsRatio and Proportion
- A1 only
- B2 only
- CBoth 1 and 2
- DNeither 1 nor 2
Explanation
(F + S)/(F - S) = 11/3 gives 3F + 3S = 11F - 11S, i.e. 14S = 8F, so F:S = 7:4; statement 1 (8:5) is false. When the son attains twice his present age, S more years pass: the ratio becomes (F + S):2S = (7/4 + 1):2 = 11:8, so statement 2 is true. Hence option B.