Karin has two pencils. One is a good one, and the other is a cheap one. The good pencil cost $1.00 more than the cheap one. Karin spent $1.10 for both pencils. How much did her cheap pencil cost?
Answer
Five cents. The expensive pencil cost $1.05. You may have thought the answer was 10 cents, but that does not meet the requirement of the expensive pencil costing $1.00 more than the cheap pencil. If the cheap pencil cost 10 cents, the expensive pencil would only cost 90 cents more.