Question

in how many years will a sum of money triple itself, f the rate of interest is 10%

Answer 1

$Let \: the \: sum \: be \: p \: and \: time \: be \: x\\ then \: the \: estimated \: amount \: will \: be \: 3p$

$p(1 + \frac{10}{100})^{x} = 3p \\ \\ (\frac{11}{10} )^{x} = \frac{3p}{p} \\ \\ ({1.1})^{x} = 3 \\ x = \frac{3}{11} \times 10 \\ x = \frac{30}{11} \: \: \: \: \: \: \: 2 \times \frac{8}{11}$