Find the compound interest on Rs. 15625 for 9 months, at 16% per annum

1.	Find the compound interest on Rs. 15625 for 9 months, at 16% per annum, compounded quarterly.
Answer» Given, Principal = Rs. 15625 Rate = 16% per annum \(=\frac{16}{4}\) = 4% quarterly Time = 9 months \(=\frac{9}{12}\) years \(=\frac{9}{12}\times{4}\) = 3 quarters Hence, Compound interest \(={P}[({1}+\frac{R}{100})^T-{1}]\) \(={15625}[({1}+\frac{4}{100})^3-{1}]\) \(={15625}[(\frac{26}{25})^3-{1}]\) = \({15625}\times\frac{1951}{15625}\) = Rs. 1951

Find the compound interest on Rs. 15625 for 9 months, at 16% per annum, compounded quarterly.

Answer»

Given,

Principal = Rs. 15625

Rate = 16% per annum \(=\frac{16}{4}\) = 4% quarterly

Time = 9 months \(=\frac{9}{12}\) years

\(=\frac{9}{12}\times{4}\) = 3 quarters

Hence,

Compound interest \(={P}[({1}+\frac{R}{100})^T-{1}]\)

\(={15625}[({1}+\frac{4}{100})^3-{1}]\)

\(={15625}[(\frac{26}{25})^3-{1}]\)

= \({15625}\times\frac{1951}{15625}\)

= Rs. 1951