SOLUTION: I need help setting up this problem... Sarah has a motorboat that is travelling on a river with a current of 6 mph. The trip upstream takes 4.5 hrs. Also, the return trip downstre

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Question 1047809: I need help setting up this problem...
Sarah has a motorboat that is travelling on a river with a current of 6 mph. The trip upstream takes 4.5 hrs. Also, the return trip downstream takes 4 hours. How fast would Sarah’s boat be going if it were in still water.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Sarah has a motorboat that is travelling on a river with a current of 6 mph. The trip upstream takes 4.5 hrs. Also, the return trip downstream takes 4 hours. How fast would Sarah’s boat be going if it were in still water.
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Upstream DATA:
time = 4.5 hrs ; rate = b-6 mph ; distance = t*r = 4.5(b-6) miles
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Downstream DATA:
time = 4 hours ; rate = b+6 mph ; distance = t*r = 4(b+6) miles
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Equation:
distance up = distance down
4.5b - 27 = 4b + 24
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0.5b = 51
Boat speed in still water = b = 102 mph
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Cheers,
Stan H.
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