Q. In what time will Rs. 1000 becomes Rs. 1331 at 10% per annum compounded annually?
Answer: 3 years
Notes: Let the required time be n years, Then, $latex 1331=1000\left ( 1+\frac{10}{100} \right )^{n}&s=1$ $latex =>\frac{1331}{1000}=\left ( \frac{10+1}{10} \right )^{n}&s=1$ $latex =>\left ( \frac{11}{10} \right )^{n}=\left ( \frac{11}{10} \right )^{3}&s=1$ $latex =>n=3$ Hence option [B] is the right answer.

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