The simple interest on a sum of money at 10% per annum for 2 years is Rs. 8,100. What would be the compound interest (in Rs.) on the same sum for the same period at 15% p.a, when the interest is compound yearly?

Solution (By Examveda Team)

R = 10%, T = 2 year, SI = Rs. 8100
$$8100 = \frac{{{\text{P}} \times 10 \times 2}}{{100}}$$
40500 = P
Now same principal
R% = 15%
T = 2 year
CI = ?
$$15\% = \frac{3}{{20}}$$

$${\text{CI}} = \frac{{129 \times 405}}{4} = 13061.25$$