Question

Tick (✓) the correct answer:
Ravi buys some toffees at 5 for a rupee and sells them at 2 for a rupee. His gain per cent is
(a) 30%
(b) 40%
(c) 50%
(d) 150%

Answer 1

(d) 150%

​ $$\begin{gathered} \mathrm{L}.\mathrm{C}.\mathrm{M}\mathrm{of}5\mathrm{and}2=\left(5\times 1\times 2\right)=10 \\ \mathrm{Let}10\mathrm{be}\mathrm{the}\mathrm{number}\mathrm{of}\mathrm{toffees}\mathrm{bought}. \\ \mathrm{CP}\mathrm{of}5\mathrm{toffees}=\mathrm{Rs}1 \\ \mathrm{CP}\mathrm{of}1\mathrm{toffee}=\mathrm{Rs}\left(\frac{1}{5}\right) \\ \therefore \mathrm{CP}\mathrm{of}10\mathrm{toffees}=\mathrm{Rs}\left(\frac{1}{5}\times 10\right) \\ =\mathrm{Rs}2 \\ \mathrm{SP}\mathrm{of}2\mathrm{toffees}=\mathrm{Rs}1 \\ \mathrm{SP}\mathrm{of}1\mathrm{toffee}=\mathrm{Rs}\left(\frac{1}{2}\right) \\ \therefore \mathrm{SP}\mathrm{of}10\mathrm{toffees}=\mathrm{Rs}\left(\frac{1}{2}\times 10\right) \end{gathered}$$
$=Rs.5$
$$\begin{gathered} \mathrm{Gain}=\mathrm{Rs}\left(5-2\right) \\ =\mathrm{Rs}3 \\ \mathrm{Gain}\mathrm{percentage}=\left(\frac{\mathrm{gain}}{\mathrm{CP}}\times 100\right)\% \\ =\left(\frac{3}{2}\times 100\right)\% \\ =150\% \end{gathered}$$