SOLUTION: trinas boat travels 20km/h in still water. a river has a current that flows at a rate of 5km/h. trina travels in her boat downstream for 1 km and then returns to her starting poi

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Question 912539: trinas boat travels 20km/h in still water. a river has a current that flows at a rate of 5km/h. trina travels in her boat downstream for 1 km and then returns to her starting point. her average rate in km/h for the entire trip is
Found 2 solutions by ewatrrr, richwmiller:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
1m%2F%2825kmph%29+%2B+1m%2F%2820kmph%29 = total time = 45%2F500
avg rate = (2km/(45/500) = 1000/45 = 22.22kmph

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
If the boat goes 20+5 (25) with the current it goes 20-5 (15) against the current
t=d/r
1/25+1/15=40/375 Total time
r=d/t
r=2 km/(40/375)
2*375/40=375/20=18.75 kph average