A sum of Rs. 800 amounts to Rs. 920 in 3 years at the simple interest rate. If the rate is increased by 3% p.a. What will be the sum amount to in the same period ?

Explanation:-

$$\eqalign{ & {\text{Increased interest in 3 years}} \cr & {\text{ = 3}} \times {\text{3}} \cr & {\text{ = 9% }} \cr & {\text{Hence increased amount}} \cr & {\text{ = }}\frac{{800 \times 9}}{{100}} \cr & = {\text{Rs}}{\text{. }}72 \cr & {\text{Total amount}} \cr & {\text{ = }}\left( {920 + 72} \right) \cr & = {\text{Rs}}{\text{. }}992 \cr}$$