Question

At what rate percent compound interest does a sum of money become nine fold in 2 years?​

Answer 1

Answer:

Rate = 200%

Step-by-step explanation:

Let Principal (P) = Rs x,

Amount (A) = Rs 9x (given)

Number of times interest paid (n) = 2

Let Rate of interest = r,

$A=\:P\left(1+\frac{R}{100}\right)^n$

$9x\:=\:x\:\left(1+\frac{r}{100}\right)^2$

$9\:=\:\:\left(1+\frac{r}{100}\right)^n$

$\sqrt{9}\:=\:\:\left(1+\frac{r}{100}\right)^n<p><p>$

$3-1\:=\frac{r}{100}$

$2\:=\frac{r}{100}$

$2\times 100\:=r$

$r=\:200\%$