Problema Solution

A boat traveled downstream a distance of 75mi and then came right back. If the speed of the current was 8mph and the total trip took 5 hours, find the average speed of the boat relative to the water.

Answer provided by our tutors

We shell use the formula


t = s / v where t is time, s is the distance and v is the speed.


Let c = 8mph be the speed of the current and 'b' be the speed of the boat. Solve the following for b:


75 / (b+8) + 75 / (b−8) = 5


b = -2


b = 32


Since the speed of the boat must be a positive number then solution we are looking for is 32 mph.


The speed of the both relative to the water is 32mph.