Question 883786
It took betty 4.5 hrs to drive to her mother's house on Sat morning. On her return trip on Sun night, traffic was heavier, so her trip took her 5 hrs. Her average speed on Sun was 7 mph slower than Sat. What was her average speed on Sun.
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let x=speed on Saturday
x-7=Speed on Sunday
distance=travel time*speed (equal for both trips)
4.5x=5(x-7)
4.5x=5x-35
0.5x=35
x=70
x-7=63
average speed on Sun=63 mph