The ages of two sisters A and B are in the ratio 7:6. After 12 years the ratio of their ages will be 9:8. Find the difference between their ages.

A5 years

B4 years

C6 years ✓ Correct

D8 years

Correct answer: (C) 6 years

Explanation

The difference in ages is 6 years.

let the ages be 7x and 6x.

(7x + 12)/(6x + 12) = 9/8.

8(7x + 12) = 9(6x + 12), so 56x + 96 = 54x + 108.

2x = 12, x = 6.

difference = 7x - 6x = x = 6 years.

Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.