Answer:
40 miles an hour
Explanation:
Note that the speed given to you is in 1/2 an hour. To get 1/2 hour to become 1 hour, multiply by 2.
20 = 1/2h
20(2) = (1/2)h(2)
Simplify. Isolate the h. What you do to one side, you do to the other
20(2) = h
h = 40
40 mph is your answer
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