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Julie drives 100 mi to Grandmother’s house. On the way to Grandmother’s, Julie drives half the distance at 40 mph and half the distance at 60 mph. On her return trip, she drives half the time at 40 mph and half the time at 60 mph.
a. What is Julie’s average speed on the way to Grandmother’s house?
b. What is her average speed on the return trip?
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