Question

A man purchased 9 books.Cost 2 books is RS.50. How much he has to pay for shopkeeper

Answer 1

In this question you just have to apply Unitary method,
Cost of 2 books = Rs 50
then, cost of 1 book = 50/2 = Rs 25
So, Cost of 9 books = Rs 225.
Thus, He has to pay Rs 225 to the shopkeeper.

Answer 2

cost of 2 books is 50 rs
cost of 9 books is 50*9/2=225 rs
so he has to pay 225 rs