Problema Solution
The current in a stream moves at a speed of 7
mph
.
A boat travels 6
mi
upstream and 6
mi
downstream in a total time of 16
hr. What is the speed of the boat in still​ water?
Answer provided by our tutors
Let
c = 7 mph the current
v = the speed of the boat in still water, v>=0
v - c = the speed of the boat upstream
v + c = the speed of the boat downstream
d = 6 mi the distance traveled in each direction
t = 16 hr the total time of the travel
Since speed = distance/time follows time = distance/speed:
d/(v - c) + d/(v + c) = t
6/(v - 7) + 6/(v + 7) = 16
........
click here to see the equation solved for v
........
v = 7.39 mph approximately
The speed of the boat in still​ water is 7.39 mph.