Compound Interest Practice Test 3

Simple interest for the first six months when principal is Rs 100
$\mathit{S}\mathit{I}=\frac{\mathit{P}\times \mathit{R}\times \mathit{T}}{100}$ $=100\times \frac{6}{12}\times \frac{10}{100}=5$
Simple Interest for the last six months when principal is equal to (100 + 5) = Rs 105
$\mathit{S}\mathit{I}=105\times \frac{6}{12}\times \frac{10}{100}$ = Rs 5.25
Simple interest for one year = Rs 10.25
Time T = 1 year
Principal P = Rs 100
$\mathit{R}=\frac{\mathit{S}\mathit{I}\times 100}{100\times 1}$ $=\frac{10.25\times 100}{100\times 1}=10.25\%$