The price of the book is marked 20% above the Cost Price. If the marked price of the book is Rs. 180, then what is the cost of the paper used in a single copy of the book?
Answer: B
Let the Cost Price (CP) be x. The Marked Price (MP) is 20% above CP. So, MP = 1.20 * CP.
180 = 1.20 * CP => CP = 180 / 1.2 = Rs. 150.
The cost of paper is 25% of the total cost price.
Cost of paper = 25% of 150 = 0.25 * 150 = Rs. 37.50.