Categories

# [Smart Math] Ratio Proportion Problem 32

Here’s and example of a SMART MATH problem for RATIO PROPORTION.

### Problem

The sum of present ages of A, B and C is 90 years. 6 years ago their sum were in the ratio 1 : 2 : 3. What is the present age of C?

1. 24 years
2. 30 years
3. 32 years
4. 42 years
5. 60 years

### The Usual Method

Sum of present ages of A, B and C = 90 years. Hence sum of ages of A, B and C 6 years ago was = 90 – (6 x 3) = 72 years

This divided in the ratio of 1 : 2 : 3.

Hence age of C 6 years ago = $\frac{3}{1+2+3}\times 72=$ 36 years.

Hence C’s present age = 36 + 6 = 42 years

(Ans: 4)

Estimated Time to arrive at the answer = 45 seconds.