Question

On what sum will be the compound interest at 15/2% per annum for three years compounded annually be 3101.40.

Answer 1

Let P be principle
hence
CI=
$p(1 + \frac{r}{100} ) {}^{n} - p$
$3101.40 = p {(1 + \frac{15}{100 \times 2} })^{3} - p \\ 3101.40 = {p( \frac{50 + 3}{50}) }^{3} - p \\ \\ 3101.40 = \frac{148877}{125000} p - p \\ 3101.40 = \frac{23877}{125000} p \\ \\ p = 16236.33$
Hope this helps you.