Question

A motorboat maintained a constant speed of 1414 miles per hour relative to the water in going 4545 miles upstream and then returning. The total time for the trip was 7.07.0 hours. Use this information to find the speed of the current.

Answer 1

Answer;

speed of current=4 mph

Explanation and solution;

let c=speed of current

14-c=speed of boat upstream

14+c=speed of boat downstream

travel time=distance/speed

therefore;

45/(14-c) + 45/(14+c) = 7

6300+14c+630-14c=7(14-c)(14+c)

1260=7(196-c^2)

1260=1372-7c^2

180=196-c^2

c^2=16

c=4

speed of current=4 mph