Answer: approximately 8.5714 mph
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Work Shown:
(1 mile)/(7 minutes) = (x miles)/(1 hour)
(1 mile)/(7 minutes) = (x miles)/(60 minutes)
1/7 = x/60
1*60 = 7*x .... cross multiply
60 = 7x
7x = 60
x = 60/7 .... divide both sides by 7
x = 8.5714