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Homework Help: Simple constant velocity question

  1. Oct 3, 2007 #1
    7. Q: "If you must average 60 km/h for a 90 km trip, and you only average 40 km/h for the first 40 km, what velocity must you average the rest of the way?"


    90 km 60km/h 1.5h
    d v t

    40 km 40 km/s 1h
    d v t

    50 km ? 0.5h (1.5-1h = 0.5h)
    d v t

    v = d/t = 50km/0.5h = 100 km/h

    Is this the right answer and is it the right way of solving it?
  2. jcsd
  3. Oct 3, 2007 #2


    User Avatar
    Homework Helper

    Yes, looks right to me.
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