Question

In what time will Rs.$1000$ amount to Rs.$1331$ at $10$% p.a. compound interest?

• A. $4$ years
• B. $3$ years
• C. $2$ years
• D. $1$ year

Answer 1

The correct option is B $3$ years

$\Rightarrow$ We have, $P=Rs.1000,A=Rs.1331$ and $R=10\%$

$\Rightarrow$ We know, $A=P(1+\frac{R}{100}{)}^n$

$\Rightarrow$ $1331=1000(1+\frac{10}{100}{)}^n$

$\Rightarrow$ $(\frac{11}{10}{)}^n=\frac{1331}{1000}$

$\Rightarrow$ $(\frac{11}{10}{)}^3=\frac{1331}{1000}$

$\therefore$ $n=3years.$