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  1. #1
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    speed question

    It took a crew 80 min to row 3 km upstream and back again. If the rate of flow of the stream was 3km/h, what was the rowing rate of the crew?
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  2. #2
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    Quote Originally Posted by andrewpark2 View Post
    It took a crew 80 min to row 3 km upstream and back again. If the rate of flow of the stream was 3km/h, what was the rowing rate of the crew?
    Total distance is 3 km (1.5 km each way)
    Total time is 4/3 hr (80 min)
    Rate of steam is 3 km/hr

    rate of boat downstream = b + 3
    rate of boat upstream = b - 3

    d = rt

    t=\frac{d}{r}

    \frac{1.5}{b+3} + \frac{1.5}{b-3}=\frac{4}{3}

    Does that sound reasonable?
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