The present ages of A and B are in the ratio 6 : 4. Five years ago their ages were in the ratio 5 : 3. Find their present ages.

1. 42, 28
2. 36, 24
3. 30, 20
4. 25, 15

Answer: 30, 20

Explanation: ( 6x – 5) : ( 4x – 5) = 5 : 3
6x – 5 / 4x – 5 = 5/3
18x – 15 = 20x – 25
2x = 25 – 15
2x = 10
x = 5
Present age = 6 ×5 or 30 & 4 × 5 or 20