# A borrows Rs.800 at the rate of 12% per annum simple interest and B borrows Rs.910 at the rate of 10% per annum, simple interest. In how many years will their amounts of debt be equal? (1) 18 years (2) 20 years (3) 22 years (4) 24 year

Let us consider after t year amount is equal.

Consider an equation.

$800 + \frac{800\times 12\times t}{100}= 910 + \frac{910\times 10\times t}{100}$

⇒ 800 + 96t = 910 + 91t

⇒ 5t = 110

⇒ t = 22 years

∴ After 22 years the amount will be equal.