Question

A book seller bought $200$ textbooks for Rs. $12000$. He wanted to sell them at a profit so that he get $20$ books free. At what profit per cent should he sell them?

• A. $10\%$
• B. $20\%$
• C. $30\%$
• D. $40\%$

Answer 1

The correct option is A $10\%$

C.P. of $200$ textbooks $=$ Rs. $12000$

C.P. of $1$ textbook $=$ Rs. $\frac{12000}{200}=$ Rs. $60$
Profit $=$ C.P. of $20$ textbooks
$\therefore$ S.P. of $200$ textbooks $=$ C.P. of $200$ textbooks $+$ C.P. of $20$ textbooks $=$ C.P. of $220$ textbooks
$\therefore$ S.P. of $200$ textbooks $=220\times$ Rs. $60=$ Rs. $13200$
$\therefore$ Profit $\%$ $=\frac{(13200-12000)}{12000}\times 100=\frac{1200}{12000}\times 100=10\%$