A cabin cruiser travels 20 miles in the same time that a pow

A cabin cruiser travels 20 miles in the same time that a power boat travels 40 miles. The cruiser travels 5 mph slower than the power boat. Find the speed of each boat.

Solution

Cruiser DATA:
distance = 20 miles ; rate = x-5 mph ; time = 20/(x-5) hrs
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Power boat DATA:
distance = 40 miles ; rate = x mph ; time = 40/x hrs
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Equation:
time = time
20/(x-5)= 40/x
20x = 40(x-5)
20x = 40x - 200
-20x = -200
x = 10 mph (speed of the power boat)
x-5 = 5 mph (speed of the cruiser)