Question

The present age of Jacob’s father is three times that of Jacob. After 5 years, the sum of their ages would be 70 years. What's their present ages?

• A. 15 years and 45 years
• B. 45 years and 25 years
• C. 25 years and 35 years
• D. 45 years and 12 years

Answer 1

The correct option is A 15 years and 45 years

Let,
Jacob’s age be $x$ years and his father's age be $y$ years.

Given that,
present age of Jacob’s father is three times that of Jacob i.e.
$y=3x$...(i)

After 5 years, the sum of their ages would be 70 years.
$x+5+y+5=70$....(ii)

using (i) in (ii),
$\Rightarrow x+10+3x=70$
$\Rightarrow 4x=60$
$\Rightarrow x=15$

Putting $x=15$ in (i), we get $y=45$.

Thus, the age of Jacob is 15 years and Jacob's father is 45 years.