Q. A sum of 3200 Rs. invested at 10% per annum compounded quarterly amounts to 3362 Rs. Compute the time period.
Answer: $latex \frac{1}{2}\ year&s=1$
Notes: $latex A = P \left ( 1+\frac{R}{100} \right )^{T}&s=1$ $latex => \frac{3362}{3200} = \left ( 1+\frac{10}{400} \right )^{4t}&s=1$ $latex => \frac{1681}{1600} = \left ( \frac{41}{40} \right )^{4t}&s=1$ $latex => \left ( \frac{41}{40} \right )^{2} = \left ( \frac{41}{40} \right )^{4t}&s=1$ $latex => 4t = 2,\ t = \frac{1}{2}\ year&s=1$ Hence option [A] is correct answer.

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