The ratio of present ages of N and R is 5 : 3. After 4 years, their ages will be in the ratio of 3 : 2. What is the present age of R?
Show answer & explanation
Correct answer: B
Explanation
Let N = 5x and R = 3x.
After 4 years:
(N + 4) : (R + 4) = 3 : 2
5x + 4 / 3x + 4 = 3 : 2
(5x + 4)2 = 3( 3x + 4)
x = 4
R's age:
R = 3x = 3 × 4 = 12 years