Question

How to solve this sum that I had wrote down.
Calculate the amount and compound interest on Rs 10800 for 3 years at 12% per annum compounded annually.

Answer 1

Dear student
$$\begin{gathered} \mathrm{Principal},\mathrm{P}=\mathrm{Rs}10800 \\ \mathrm{Rate}\mathrm{of}\mathrm{interest},\mathrm{R}=12\% \\ \mathrm{Time},\mathrm{n}=3\mathrm{years} \\ \mathrm{We}\mathrm{know}\mathrm{that} \\ \mathrm{Amount},\mathrm{A}=\mathrm{P}{\left(1+\frac{\mathrm{R}}{100}\right)}^{\mathrm{n}} \\ \mathrm{A}=10800{\left(1+\frac{12}{100}\right)}^3 \\ \mathrm{A}=10800{\left(\frac{100+12}{100}\right)}^3 \\ \mathrm{A}=10800{\left(\frac{112}{100}\right)}^3 \\ \mathrm{A}=\mathrm{Rs}15173.22 \\ \mathrm{So},\mathrm{compound}\mathrm{interest}=\mathrm{Amount}-\mathrm{Principal}=\mathrm{Rs}15173.22-\mathrm{Rs}10800 \\ =\mathrm{Rs}4373.22 \end{gathered}$$
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