Question

At what rate percent per annum compound intetest, wilJ,_R�. 10,000 amount to Rs. 13,310 in

three years ?

(A)

Answer 1

$\: \: \: \: \: \: \: \: \: \: \: Your \: \: \: \: \: Answer \\ - - - - - - - - - - - - -$

$Given, \\ \\ P = 10000 \\ \\ A = 13310 \\ \\ T = 3 \: years$

$Let \: \: the \: \: rate \: \: be \: \: r\% \: per \: \: annum$

$Now, \: \: we \: \: know \: \: that \\ \\ A = P \times (1 + \frac{r}{100} ) {}^{t}$

$= > 13310 = 10000 \times (1 + \frac{r}{100} ) {}^{3}$

$= > \frac{13310}{10000} = (1 + \frac{r}{100} ) {}^{3 }$

$= > ( \frac{11}{10} ) {}^{3} = (1 + \frac{r}{100} ) {}^{3}$

$= > \frac{11}{10} = 1 + \frac{r}{100} \\ \\ = > \frac{11}{10} - 1 = \frac{r}{100}$

$= > \frac{11 - 10}{10} = \frac{r}{100} \\ \\ = > \frac{1}{10} = \frac{r}{100}$

$= > 10r = 100 \\ \\ = > r = \frac{100}{10} \\ \\ = > r = 10$

$hence \: \: the \: \: rate \: \: is \: \: 10\% \: \: per \: \: annum$