Find the compound interest on ₹8000 at 15% per annum for 2 years 4 months, compounded annually. (C.P.O., 2007) · ABC26GN4122

Time $=2$ years 4 months $=2\frac{4}{12}$ years $=2\frac{1}{3}$ years. ∴ Amount $=₹\left[8000 \times\left(1+\frac{15}{100}\right)^{2} \times\left(1+\frac{\frac{1}{3} \times 15}{100}\right)\right]=₹\left(8000 \times \frac{23}{20} \times \frac{23}{20} \times \frac{21}{20}\right)=₹11109$. ∴ C.I. $=₹(11109-8000)=₹3109$.