SOLUTION: how to solve this problem a speed boat travels at a rate of 20 KPH in still water. It travels 55 Km. upstream in the same time that it travels 90 KM downstream. What is the rate of

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Question 591922: how to solve this problem a speed boat travels at a rate of 20 KPH in still water. It travels 55 Km. upstream in the same time that it travels 90 KM downstream. What is the rate of the current
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how to solve this problem a speed boat travels at a rate of 20 KPH in still water. It travels 55 Km. upstream in the same time that it travels 90 KM downstream. What is the rate of the current
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Upstream DATA:
rate = (20-c)km/h ; distance = 55 km ; time = d/r = 55/(20-c) hrs.
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Downstream DATA:
rate = (20+c)km/h ; distance = 90 km ; time = 90/(20+c) hrs.
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Equation:
time up = time down
55/(20-c) = 90/(20+c)
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55*20 + 55c = 90*20 - 90c
145c = 35*20
c = (7/29)*20
c = 140/29 = 4.83 km/h (rate of the current)
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Cheers,
Stan H.
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