Question

kavita borrowed ₹80,000 from bank at the rate of 10% per annum .Find the amount payable by her after 1/2 yearly if the interest is being compounded half-yearly.​

Answer 1

$\huge \bold \blue{solution}$

$\small \bold{amount \: = p(i \: + \: \frac{r}{100})^{n}}$

$\small \bold{ = 8000(1 + \frac{5}{100})}^{3}$

$= 80000( \frac{20 + 1}{20})^{3}$

$= 80000( \frac{21}{20})^{3}$

$= 80000 \times \frac{21}{20} \times \frac{21}{20} \times \frac{21}{20}$

$= 10 \times 9261$

$\small \bold \purple{amount \: = \: rupees \: 9210}$

Compound Interest = Amount - Principle

= 92610 - 80000

$\small \bold \blue{= \: rupees \: 12610}$

Answer 2

$\huge \mathcal \colorbox{pink}{solution}$

$\bold{amount \: = \: p (i \: + \frac{r}{100} )} {}^{n}$

$\bold{= 80000(1 + \frac{5}{100})^{3}}$

$\bold{ = 80000( \frac{20 + 1} {20})}^{3}$

$\bold{= 80000 \: ( \frac{21}{20})^{3}}$

$\bold{= 80000 \: \frac{21}{100} \times \frac{21}{100} \times \frac{21}{100}}$

$\bold{= 10 \times 926}$

$\bold \red{amount} \: = \bold{\: rupees \: 9210}$

$compound \: interest \: = \: amount \: - \: principal \:$

$\bold{= 92610 - 80000}= \bold \blue{ rupees \: 12610}$