Question

A student bought some books for Rs.60. Had he bought 2 booka less for the
same amount the cost of each book would have been I rapee more. Find the
number of books bought by the student​

Answer 1

Answer:

A student bought some books for Rs.60. Had he bought 2 books less for the  same amount the cost of each book would have been I rupee more. The  number of books bought by the student​ is 12

Step-by-step explanation:

Let x be the cost of one book.

The number of books that can be bought by rs 60 at rs x each is given by:

Books = 60/x

When the price of a book is increased by 1 rupee, the cost becomes:

rs (x + 1)

Now, with rs 60 you can purchase:

60/(x + 1)

If the student buys at x + 1, he gets 2 books less. So, we write this as:

60/x = 60/(x + 1) + 2

60(x + 1) = 60x + 2(x + 1)x

60x + 60 = 60x + 2x² + x

Collecting the like terms together we have:

2x² + x - 60 = 0

Applying quadratic dormula we have:

x = [-1±√(1 + 4 × 60 × 2)]/4

x = 5.2 which is approximately 5

Therefore, the cost of each book is rs 5.

The student bought:

60/5 = 12 books.

Answer 2

Step-by-step explanation:

Given  A student bought some books for Rs.60. Had he bought 2 books less for the  same amount the cost of each book would have been I rupee more. Find the  number of books bought by the student

• Let the number of books purchased for Rs 60 be x
• Therefore cost of each book is 60 / x
• If he buys two books less, then number of books = x – 2
• Therefore cost of each book = 60/x – 2
• According to question we have
• 60/x – 2 – 60/x = 1
• 60x – 60(x – 2) = (x – 2)x
• 60x – 60x + 120 = x^2 – 2x
• Or x^2 – 2x – 120 = 0
• So x^2 – 12x + 10x – 120 = 0
• Or x(x – 12) + 10(x – 12) = 0
• So x - 12 = 0 or x + 10 = 0
• So x = 12, - 10

Therefore number of books bought by the student is 12

Reference link will be

https://brainly.in/question/6229710