Question

The difference between the ages of two cousins is 10 years fifteen years agothe elder one was twice as old asthe younger one

Answer 1

Answer :

The present ages of younger one and elder one are 20 years and 30 years respectively.

Explanation :

Given : Ages of two cousins differ by 10 years. If 15 years ago the elder one will be two times as older as the younger one.

To find : Present ages of them.

Soultion :

Let the age of elder one be x years

Let the age of the younger one be y years

Difference of age between them = 10 years

=> x - y = 10

x = 10 + y ------- eq(1)

15 years ago:

The age of elder one = (x - 15) years

The age of younger one = (y - 15) years

According to the question:

(x - 15) = 2(y - 15)

10 + y - 15 = 2(y - 15)

10 + y = 2y - 30

3y - y = 10 + 30

2y = 40

y = 40/2

y = 20

Subtitute y = 14 in eq(1)

x = 20 + 10

x = 30

So the present ages of younger one and elder one are 20 years and 30 years respectively.