Question

Helen purchased 3 copies of a book online at a 20% discount. She also paid $10 for shipping that was not discounted. How much was the original price of one copy of the book if her total ended up being $40?

Answer 1

The original price of the book was $12.50

Explanation:

3x - 0.2(3x) + 10 = 40
30x - 2(3x) + 100 = 400
30x - 6x + 100 = 400
24x + 100 = 400
24x = 300
x = 12.50