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Homework Help: Simple Uniform Motion Problem

  1. Oct 21, 2015 #1
    1. The problem statement, all variables and given/known data
    Marlene rides her bicycle to her friend Jon's house and returns home by the same route. Marlene rides her bike at constant speeds of 6 mph on level ground, 4 mph when going uphill, and 12 mph when going downhill. If her total time riding was 1 hour, how far is it to Jon’s house?

    Answer = 3 miles

    2. Relevant equations

    3. The attempt at a solution



    I have tried solving for each variable independently and then substituting it, but when I do that all my terms cancel out and I am either left with 1=1 or 12=12 depending of which equation I start with.

    I understand that Marlene traveled different distances at different rates, and for different intervals of time. I know that the total distance traveled in 1 hour must be 6 miles but I can't seem to express it mathematically.
  2. jcsd
  3. Oct 21, 2015 #2


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    If Marlene travels a certain distance uphill on her way to Jon's house, does she travel this same distance uphill on her way back home?
  4. Oct 21, 2015 #3
    She would travel the same distance, but she will be going downhill where ever she initially traveled uphill.
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