The ratio of the present ages of A and B is 4:5. Five years from now, the ratio of their ages will be 5:6. What is the present age of B?
Show answer & explanation
Correct answer: B
Explanation
Given:
A : B = 4 : 5
Ratio after 5 years = 5 : 6
According to the formula:
Ages based on the ratio = 4x, 5x
A = 4x
B = 5x
After 5 years:
(4x + 5) / (5x + 5) = 5 / 6
6(4x + 5) = 5(5x + 5)
24x + 30 = 25x + 25
x = 5
B = 5x = 5 × 5 = 25 years