Question

Solve the 12th question please

Answer 1

Given:

The ratio of present ages of Sonu and Monu = 7:5

The ratio of their ages after 10 years = 9:7.

To find:

The present ages of Sonu and Monu.

Solution:

Let the present ages of Sonu and Monu are 7x and 5x respectively.

Their ages after 10 years are (7x+10) and (5x+10) respectively.

The ratio of their ages after 10 years = 9:7.

`(7x+10)/(5x+10)=(9)/(7)`

`7(7x+10)=9(5x+10)`

`49x+70=45x+90`

`49x-45x=90-70`

On further simplification, we get

`4x=20`

`x=(20)/(4)`

`x=5`

Now,

Sonu's present age =
`7x`

=
`7(5)`

=
`35`

Monu's present age =
`5x`

=
`5(5)`

=
`25`

Therefore, the present ages of Sonu and Monu are 35 and 25 respectively.