Question

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

• A. $7$
• B. $8$
• C. $9$
• D. $10$

Answer 1

The correct option is B $8$

Let the present age of Hari and Harry be $5x,7x$ years respectively.

Four years from now the age of Hari will be $5x+4$ years and that of Harry will be $7x+4$ years.

According to the problem,

$\frac{5x+4}{7x+4}=\frac{3}{4}$

or, $20x+16=21x+12$

or, $x=4$.

So present age of Hari is $20$ years and that of Harry is $28$ years.

Now absolute difference of their present age is $|28-20|=8$ years.