Answers:
2.857142 mph
4.190476 ft per second
Both values are approximate
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Work Shown:
21 min = 21/60 = 0.35 hrs which is exact
distance = rate*time
rate = distance/time
rate = (1 mile)/(0.35 hrs)
rate = (1/0.35) mph
rate = 2.857142 mph which is approximate
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21 min = 21*60 = 1260 seconds
1 mile = 5280 ft
rate = distance/time
rate = (5280 ft)/(1260 seconds)
rate = (5280/1260) ft per second
rate = 4.190476 ft per second approximately
