Question

A school had ₹1000 to buy 18 books of the same price for the library.How much did each book cost?How much money is left with the school​

Answer 1

Step-by-step explanation:

Let the shopkeeper buy x number of books. 

According to the given condition cost of x books =Rs80

Therefore cost of each book =x80

Again when he had brought 4 more books

Then total books in this case =x+4

So cost of each book in this case =x+480

According to Question, 

x80−x+480=1

x(x+4)80(x+4)−80x=1

x2+20x−16x−320=0

(x−16)(x+20)=0

x=16orx=−20

Hence the shopkeeper brought 16 books

Answer 2

Each book costs ruppees 55 and 10 ruppees is left with the school