Question

Ratio of the present ages of ‘A’ and ‘B’ is 9:16 respectively. 20 years from now, the ratio of ages of ‘B’ to ‘C’ will be 2:1. Square roots of present ages of ‘A’ and ‘C’ are in the ratio 3:2 respectively. Find the present age of ‘C’. 

A 12 years Correct Answer Incorrect Answer
B 16 years Correct Answer Incorrect Answer
C 20 years Correct Answer Incorrect Answer
D 10 years Correct Answer Incorrect Answer
E 4 years Correct Answer Incorrect Answer

Solution

Let, present age of ‘A’, ‘B’ and ‘C’ be 9x years, 16x years and m years respectively. So, √9x:√m = 3:2 Or, 9x/m = 9/4 Or, x/m = 1/4 Or, m = 4x ----(i) Again, (16x + 20):(m + 20) = 2:1 Or, 16x + 20 = 2m + 40 Or, 16x – 2m = 20 Or, 16x – 2(4x) = 20 [from (i)] Or, 16x – 8x = 20 Or, 8x = 20 Or, x = 2.5 Present age of ‘C’ = 4 × 2.5 = 10 years.

Practice Next
More Age Questions

Relevant for Exams:

ask-question