Question

if the cost of 5 exercise books is Rs22.50, determine the cost of 7 exercise books of the same price

Answer 1

cost of 5 books= 22.50
cost of 1 book= 22.50 /5
cost of 7 books =4.50 ×7=31.50

Answer 2

Here is your solution

Given:-

cost of 5 exercise books = Rs22.50

cost of 1 exercise books =22.50/5 = Rs4.5

hence

Cost of 7 exercise book =?

cost of one exercise book × 7

=4.5×7

=31.5

Hence Cost of 7 exercise book is Rs 31.5

hope it help you