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?

Explanation:

Let after t year amount will be equal.

According to the question,

800+800×12×t\100

=910+910×10×t\100

800+96t=910+91t

5t=110

t=22years

Hence, after 22 years the amount will be equal.