# Jerry was 1/3 as young as his grandfather 15 years ago. If the sum of their ages is 110, how old is Jerry's grandfather?

Apr 26, 2017

75 years

#### Explanation:

Let grandfather's age was x years 15 years ago. So Jerry's age was $\frac{x}{3}$ years 15 years ago.

Hence 15 years ago sum of their's age was 110 - 15*2 = 80 years.

So as per questions, $x + \frac{x}{3} = 80$

$\Rightarrow \frac{3 x + x}{3} = 80$

$\Rightarrow \frac{4 x}{3} = 80$

$\Rightarrow x = 80 \times \frac{3}{4} = 60$

Therefore 15 years ago grandfather's age was 60 years.

Now grandfather's age is 60 + 15 = 75 years.