Question

Q. By increasing the list price of a book by Rs510 a person can buy 10 less books for Rs1200, find the original list price of book.​

Answer 1

Answer:

Step-by-step explanation:

By increasing the list price of a book by Rs.10, a person can buy 10 books less for Rs.1200. Find the original list price of the book?

Let original book price=X

Number of books that can be bought in 1200 =1200/x

Suppose price increases by 10. New price=x+10

No of books that can be bought in new price= 1200/(x+10)

Now, this number is 10 less than the no of books that can be bought in 1200 at ‘x’ price.

So, 1200/x= 1200/(x+10) + 10

Simplifying the above we get

X^2 +30x -1200=0

This is a quadraatic equation having two solutions, 30 & -40. Ignoring negative value the answer is x=30

So orinal book price is Rs 30