Question

The sum of the age of two sister is 38. The younger sister was 4 years younger than older ten years ago. How old is the younger

Answer 1

Given:

The sum of the age of two sister is 38. The younger sister was 4 years younger than older ten years ago.

To Find:

How old is the younger?

Solution:

Present age

Let age of younger sister = X years

Age of older sister = 38 - X

Past age

Before 10 years, age of younger and older sister was:

Age of younger sister = X - 10

Age of older sister = 38 - X - 10 = 28 - X

From given question:

The younger sister was 4 years younger than older ten years ago:

X-10 = 28 - X - 4

X- 10 = 24 - X

X + X = 24 + 10

2X = 34

Means:

X = 17 years

Present age of younger sister is 17 years.