Question

Find the compound interest at the rate of 10% per annum for two years on that principal which in two years at the rate of 10% per annum gives Rs 200 as simple interest.

Answer 1

SI \[= \frac{PRT}{100}\]
\[ \therefore P = \frac{SI \times 100}{RT}\]
\[ = \frac{200 \times 100}{10 \times 2}\]
 = Rs 1, 000
A = P \[\left( 1 + \frac{R}{100} \right)^n \]
\[ = 1, 000 \left( 1 + \frac{10}{100} \right)^2 \]
\[ = 1, 000 \left( 1 . 10 \right)^2 \]
 = Rs 1, 210
Now, 
CI = A - P
 = Rs 1, 210 - Rs 1, 000
 = Rs 210