Question

If the list price of a book is reduced by Rs. 5, then a person can buy 5 more books for Rs. 300. The original cost of
the book is
Rs. 15
ORs. 20
Rs.25
Rs.30​

Answer 1

Answer:

20

Step-by-step explanation:

Let the price of a book be 'a'.

 Total price = number of books * a

  300/a = number of books

When the price is reduced by 5: new price = a - 5.

 Number of books = (300)/(a - 5)

then, he had enough money to buy 5 more  books:

⇒ (300)/(a - 5) - (300/a) = 5

⇒ 300[ 1/(a - 5) - 1/a] = 5

⇒ 300[ a - a + 5 ]/a(a - 5) = 5

⇒ 300 = a(a - 5)

⇒ 20*15 = a(a - 5)

⇒ 20(20 - 5) = a(a - 5)

   Compare both, a = 15

Price of book is 20