Question

what is the cost to company amount of rupees 12000​

Answer 1

$\mathfrak{ \green{ \underline{ \underline{answer}}}} \\ \bf{ \green{principal = rs12000}} \\ \bf{amount \: = rs15972} \\ \bf{time = prinicpal \bigg(1 + \frac{r}{100} \bigg) {}^{3} } \\ \mapsto \bf{15972 = 12000 \bigg(1 + \frac{r}{100} \bigg) {}^{3} } \\ \mapsto \bf{ \frac{15972}{12000} = \bigg(1 + \frac{r}{100} \bigg) {}^{3} = \frac{1331}{100} = \bigg(1 + \frac{r}{100} \bigg) {}^{3} } \\ \bf{ \bigg ( \frac{11}{3} \bigg) {}^{3} = \bigg(1 + \frac{r}{100} \bigg) {}^{3} } \\ \mapsto1 + \frac{1}{10} = 1 + \frac{r}{100} \\ \mapsto \bf{ \: \frac{r}{100} = \frac{1}{10} } \\ \mapsto \bf{ r = \frac{1}{10} \times 100 = 10\% } \\ \bf{ \purple{rate \: of \: intrest \: per \: half \: year \: = 10\%}} \\ \therefore \blue{ \bf{rate \: of \: intrest \: per \: annum = 10 \times 2 = 20\%}}$