SSC Sample Paper Mock Test-10 SSC CGL Tear-II Paper-1

       A shopkeeper purchased a chair marked at Rs. 800, at two successive discounts of 10% and 15% respectively. He spent Rs. 28 on transportation sold the chair for Rs. 800. His gain per cent is

A) 40%

B) 30%

C) 25%

D) 14%

Correct Answer: C

Solution :

Purchase price \[=(800-10%\,\,\text{of}\,\,800)-15%\]

of \[(800-10%\,\,\text{of}\,\,\text{800)}\]

\[=\left( 800-\frac{10}{100}\times 100 \right)-15%\]of \[\left( 800-\frac{10\times 800}{100} \right)\]

\[=(800-80)-15%\]of\[(800-80)=720-\frac{15}{100}\times 720\]

\[=720-108\]= Rs. 612

Total cost price = 612 + 28 = Rs. 640

Gain per cent

\[=\frac{800-640}{640}\times 100=\frac{160}{640}\times 100=25%\]