The ratio between the son and mother is 1:3. After five years, the ratio of their age becomes 3:7. What are the ages of the son and mother?
Show answer & explanation
Correct answer: A
Explanation
Given:
Son : Mother = 1 : 3
By the formula:
Let
Son = x
Mother = 3x
After 5 years
(x + 5) : (3x + 5) = 3 : 7
7(x + 5) = 3(3x + 5)
7x + 35 = 9x + 15
20 = 2x
x = 10
Son = 10
Mother = 30
Son's age = 10 years
Mother's age = 30 years