T1 = 130mi/(65mi/h) = 2 h.
T2 = 130mi/(80mi/h) = 1.625 h.
Time saved = T1-T2.
Richard is driving home to visit his parents. 130 mi of the trip are on the interstate highway where the speed limit is 65 mph . Normally Richard drives at the speed limit, but today he is running late and decides to take his chances by driving at 80 mph .
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