Question

Mark (✓) against the correct answer
The simple interest on a sum for 5 years is $\frac{2}{5}$ of the sum. The rate per cent per annum is

(a) 10%
(b) 8%
(c) 6%
(d) $12\frac{1}{2}\%$

Answer 1

(b) 8%

$$\begin{gathered} \begin{array}{l}\text{Time=5 years}\\ \text{Simple interest=}\frac{\text{2}}{\text{5}}\text{P}\\ =>\frac{\text{P×Rate×Time}}{\text{100}}\text{=}\frac{\text{2}}{\text{5}}\text{P}\\ =>\frac{\text{Rate×5}}{\text{100}}\text{=}\frac{\text{2}}{\text{5}}\\ \end{array} \\ \Rightarrow Rate=\frac{2\times 100}{5\times 5} \\ \text{=>Rate=8\%} \end{gathered}$$