Problem: A merchant buys goods at 25% off the list price. He desires to mark the goods so that he can give a discount of 20% on the marked price and still clear a profit of 25% on the selling price. What per cent of the list price must he mark the goods?
Answer Choices:
A. 125%
B. 100%
C. 120%
D. 80%
E. 75%
Solution:
Let C= merchant's cost, L= list price, M= marked price, S= selling price, and P= profit. Then
C=L−41L=43L,S=M−51M=54M,S=C+P54M=43L+41⋅54M,M=35⋅43L=45L