Question

If the list price of a book is reduced by Rs. $5$ a person can buy $5$ more books for Rs. $300$. Find the original list price of the book.

• A. $15$
• B. $10$
• C. $20$
• D. $25$

Answer 1

Answer: (C)

$20$

Let the original price of the books be $x$

$\therefore$ new price $=x-5$

Given, $\frac{300}{x-5}-\frac{300}{x}=5$

$60x-60x+300=x^2-5x$

$x^2-20x+15x-300=0$

$(x-20)(x+15)=0$

$x$ cannot be negative, i.e, $x=20$