Question 901866: A boat can travel six miles downstream in 40 minutes. The return trip requires an hour. Find the rate of the boat in still water. Found 2 solutions by ewatrrr, lwsshak3:Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! A boat can travel six miles downstream in 40 minutes. The return trip requires an hour. Find the rate of the boat in still water.
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let x=speed of boat in still water
let c=speed of current
x+c=speed of boat downstream
x-c=speed of boat upstream
travel time*speed=distance
..
40 min=2/3 hr
2/3*(x+c)=6
1*(x-c)=6
..
2x+2c=18
x-c=6
..
2x+2c=18
2x-2c=12
add
4x=30
x=7.5
c=x-6=1.5
rate of the boat in still water=7.5 mph
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