Question

The age of hari and harry are in the ratio 5 is to 7 four years from now the ratio of their age will be three is 24 find their present age

Answer 1

Correct Question:-

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

Solution:-

Let present age of Hari be "5M" years

and

 Present age of Harry be "7M" years.

Four years from now the ratio of their ages will be 3:4.

After 4 years,

• Age of Hari = (5M + 4) years
• Age of Harry = (7M + 4) years

According to question,

=> $\sf{\dfrac{5M\:+\:4}{7M\:+\:4}\:=\:\dfrac{3}{4}}$

Cross-multiply them

=> $\sf{4(5M\: +\: 4)\: = \:3(7M\: + \:4)}$

=> $\sf{20M\: + \:16 \:= \:21M\: +\: 12}$

=> $\sf{20M\: - \:21M \:= \:12 \:- \:16}$

=> $\sf{20M \:-\: 21M\: =\: - 4}$

=> $\sf{- M \:=\: - 4}$

=> $\sf{M \:= \:4}$

So,

Present age of Hari = 5M

=> $\sf{5(4)}$

=> $\sf{20\: years}$

Present age of Harry = 7M

=> $\sf{7(4)}$

=> $\sf{28 \:years}$

•°• Present age of Hari is 20 years 

Present age of Harry is 28 years.

Answer 2

Answer:

Hari's age is 20 and Harry's age is 28.

Step-by-step explanation:

Ratio of their present ages is 5 : 7.

It's given that after 4 years the ratio of their ages become 3 to 4.

So,

let the number be x which should be multiplied to the present age to make it equal to the age after 4 yrs.

By adding 4 yrs to the present we get :

5x + 4/ 7x + 4 which is equal to 3 : 4

solution :

⇒ 5x + 4/ 7x + 4 = 3/4

⇒ 20x + 16 = 21x + 12

⇒ 16 - 12 = 21x - 20x

⇒ 4 = x

∵ 4 = x

The age of Hari -

4 * 5= 20 yrs.

And the age of Harry -

4 * 7= 28 yrs.

:) Thank You !