The compound interest on a certain sum for 2 years at 10% per annum is Rs. 525. The simple interest on the same sum for double the time at half the rate percent per annum is = ?

Solution(By Examveda Team)

$$\eqalign{ & 10\% = \frac{1}{{10}} \cr & {\text{Let P}} = {\text{ }}{\left( {10} \right)^2} = 100 \cr & {\text{Total CI = 21 unit = 525}} \cr & {\text{1 unit = 25}} \cr & {\text{P}} = {\text{ 100 unit }} \cr & {\text{ = 100}} \times {\text{25}} = {\text{2500}} \cr & {\text{New Time = 4 years}} \cr & {\text{and new rate = 5}}\% \cr & {\text{SI = }}\frac{{2500 \times 4 \times 5}}{{100}}{\text{ }} \cr & {\text{SI = Rs. 500}} \cr} $$