SOLUTION: In testing the rate at which a polluted stream flows, a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream and 8 hrs to go upstream, between 2 points. what is
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-> SOLUTION: In testing the rate at which a polluted stream flows, a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream and 8 hrs to go upstream, between 2 points. what is
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Question 228633: In testing the rate at which a polluted stream flows, a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream and 8 hrs to go upstream, between 2 points. what is the rate of flow of the stream Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream
and 8 hrs to go upstream, between 2 points.
what is the rate of flow of the stream
:
Let r = rate of flow of the stream
then
(5.5 + r) = boat speed down stream
and
(5.5 - r) = boat speed up stream
:
Write a distance equation, distance is the same for both trips
Dist = speed * time
:
dist down = dist up
5(5.5 + r) = 8(5.5 - r)
:
27.5 + 5r = 44 - 8r
:
5r + 8r = 44 - 27.5
:
13r = 16.5
r =
r ~ 1.27 mi/hr (flow of the stream)
;
;
See if this is true; find the dist of each (should be equal)
5(5.5 + 1.27) = 33.8 mi
8(5.5 - 1.27) = 33.8 mi
