Question

The ratio of the present age of A and B is 3: 1. Five years ago, the ratio of their ages was 5: 1. The age of A (in years) after eight years will be:

• A. 30
• B. 22
• C. 38
• D. 40

Answer 1

Answer:

C. 38

Let present ages be:

• A = (3x)

• B = (x)

  Use the condition from 5 years ago

$\frac{3x - 5}{x - 5} = \frac{5}{1}$

Solve

$3x - 5 = 5(x - 5)$

3x - 5 = 5x - 25

20 = 2x
$\Rightarrow x = 10$

Present age of A

A = 3x = 30

Age of A after 8 years

30 + 8 = 38