SOLUTION: A cruise boat travels 72 miles down stream in two hours and returns upstream in 6 hours. Find the rate of the stream. D=RT so R=D/T 72/2=36 72/6=12 36-12=24 (speed of boat on s

Question 198643: A cruise boat travels 72 miles down stream in two hours and returns upstream in 6 hours. Find the rate of the stream.
D=RT so R=D/T 72/2=36 72/6=12 36-12=24 (speed of boat on still water?)
I get lost here.
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(48556) (Show Source):
You can put this solution on YOUR website!
A cruise boat travels 72 miles down stream in two hours and returns upstream in 6 hours. Find the rate of the stream.
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Down stream DATA:
distance = 72 miles ; time = 2 hrs: rate = d/t = 72/2 = 36 mph
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Up stream DATA:
distance = 72 miles ; time = 6 hrs. rate = 72/6 = 12 mph
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Equations
Down stream rate: b + c = 36 mph
Upstream rate...: b - c = 12
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Add to get 2b = 48
b = 24 mph (rate of the boat in still water)
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Substitute to find "c":
b+c = 24 + c = 36
c = 36-24 = 12 mph (speed of the current)
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Cheers,
Stan H.

Answer by Alan3354(21605) (Show Source):
You can put this solution on YOUR website!
A cruise boat travels 72 miles down stream in two hours and returns upstream in 6 hours. Find the rate of the stream.
D=RT so R=D/T 72/2=36 72/6=12 36-12=24 (speed of boat on still water?)
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Going downstream, the speed of the stream is added to the speed of the boat.
Upstream, it's subtracted.
72 = (b+s)*2
72 = (b-s)*6
b+s = 36
b-s = 12
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2b = 48
b = 24 mph (speed of boat)
s = 12 mph (speed of stream)