Answer:
25 miles per hour
Explanation:
distance / time = 25 miles per hour
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The ratio of distance to time is speed. The speed of the trolley is given in the problem statement as 25 mph. It can be expressed in a variety of other units. In this problem, the desired units of time and distance for the equation are not specified, so we have given the speed in the units in which it is described by the problem statement.