AP Calculus Free-Response Questions

Wilma is tiling her bathroom with tiles that measure 1 foot along each side. The bathroom is 15 feet long and 10 feet wide. She can lay 30 tiles per hour. Which of the following can be used to find the total number of hours it will take Wilma to cover the floor with tiles? A. 15 × 30 ÷ 10 = 45 hours . B. 15 + 10 ÷ 30 = 0.5 hour… ................
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