Question

A dealer marks his goods at $30\%$ above the cost price and allows a discount of $20\%$ on the marked price. Find his gain or loss per cent.

Answer 1

Let C.P. be Rs. $x$ $\Rightarrow M.P.=x+\frac{30}{100}x=\frac{13x}{10}$

$\Rightarrow S.P.=\frac{13x}{10}(1-\frac{20}{100})=\frac{13x}{10}\left(\frac{4}{5}\right)=\frac{52x}{50}$

$\Rightarrow$ Gain $\%=\frac{S.P-C.P}{C.P}\times 100=(\frac{S.P}{C.P}-1)100=(\frac{52}{50}-1)100$

$=2\times 2\%=4\%$