Question

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

Answer 1

I think it's 200 % if we take p as 9p

Answer 2

Answer:

$r = 200\%$

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,

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

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

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

$\implies \sqrt{9} = \left(1+\frac{r}{100}\right)</p><p>$

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

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

$\implies 2\times 100=r$

$\implies r = 200\%$

Therefore,

$r = 200\%$

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