# A man is four times as old as his son. In five years he will be only three times as old as his son. What is the man's present age?

May 7, 2018

Present age of man = 40 years

#### Explanation:

Let the present age of son be 'x' years.

Then, the present age of man is 4x years.

After 5 years,
Age of son = x+5
Age of man = 4x+5

Given,
age of man after 5 years = 3 times age of son after 5 years

That is,

$4 x + 5 = 3 \left(x + 5\right)$

$4 x + 5 = 3 x + 15$

$x = 15 - 5$

$= 10$

Thus,

Present age of man $= 4 \times 10$

$$                                    =40