Question

What rate percent of S.I. will a sum of money double itself

• A. 1/2%
• B. 8.33%
• C. both 1 &2
• D. none of these

Answer 1

The correct option is B 8.33%

In case of simple Interest, total amount is $A=P(1+\frac{rt}{100})$

Where,

P = Principal

R = Rate

T = time

After 12 year sum of money double itself ?

that is A = 2 P

Now apply the formula

$A=P(1+\frac{r\times 12}{100})$

$2P=P(1+\frac{r\times 12}{100})$

$2=1+\frac{12r}{100}$

$1=\frac{12r}{100}\therefore r=\frac{100}{12}=8\frac{1}{3}\%$