Going 46 mph faster for 2 hours, Mary closed a (46 mi/h)×(2 h) = 92 mile gap. That gap was created in 3 hours by Sandy going ...
(92 mi)/(3 h) = 30 2/3 mi/h
Sandy's average speed was 30 2/3 mph.
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<em>Comment on the situation</em>
We wonder what sort of road and traffic situation would allow Mary to go 76 2/3 mph in downtown Durham, while Sandy traversed the same route at 30 2/3 mph.
