Question

The age of Hari and Harry are in the ratio 5:7 . Four year from now the ratio of their ages will be 3:5. Find there percentage age.

Answer 1

Correct Question :-

The age of Hari and Harry are in the ratio 5 : 7 . Four year from now the ratio of their ages will be 3 : 4. Find there present ages.

Answer :-

Present age of Hari is 20 years and the present age of Harry is 28 years

Solution :-

Ratio of present ages of Hari and Harry = 5 : 7

Let the present ages of Hari be '5x' years and let the present age of Harry be '7x years'

Four years from now

Age of Hari = (5x + 4) years

Age of Harry = (7x + 4) years

Ratio of Hari and Harry four years from now = 3 : 5

⇒ (5x + 4)/(7x + 4) = 3/4

By Cross multiplication

⇒ 4(5x + 4) = 3(7x + 4)

⇒ 20x + 16 = 21x + 12

⇒ 16 - 12 = 21x - 20x

⇒ 4 = x

⇒ x = 4

Present age of Hari = 5x = 5(4) = 20 years

Present age of Harry = 7x = 7(4) = 28 years

Therefore present age of Hari is 20 years and the present age of Harry is 28 years.

Answer 2

✿━━━━@♥ℳg━━━━✿

$\boxed{Explained\:Answer}$

______________________________

✿━━━━@♥ℳg━━━━✿

Given ages of Hari and Harry = 5:7

 Let the ages of Hari and Harry be 5x

and 7x years 4 year laters age of Hari

= 5x + 4 years ,

Given that,4 year laters age of Harry

= 7x + 4 years

Given that 4 years later

age of Hari and Harry = 3:4 

 ⇒ 20x + 16

= 21x + 12 

⇒ 21x – 20x

= 16 – 12

 ∴ x = 4.

Or

3:4 =3/4

 =5x/7x = 3/4  (division methord)

=20x+16

=21x+12

=21x-20x

=16-12 

= x=4