Problem:
Shelby drives her scooter at a speed of 30 miles per hour if it is not raining, and 20 miles per hour if it is raining. Today she drove in the sun in the morning and in the rain in the evening, for a total of 16 miles in 40 minutes. How many minutes did she drive in the rain?
Answer Choices:
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Solution:
Let be the number of minutes Shelby spent driving in the rain. Then she traveled miles in the rain, and miles in the sun. Solving results in minutes.
The problems on this page are the property of the MAA's American Mathematics Competitions