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I have a question about Calculating Avreage Speed

  1. Sep 9, 2009 #1
    The question states that Running a marathon backwards the record is 3 h 53 min 17 s and the race is 42.2 km's and im supposed to calculate avreage speed of the race in meters per second and kilometres per hour I found a way to convert the record into just hours and I divided by 42.2 and the answer was completely wrong because according to the book its 10.9km/h and 3.01m/s does anyone have any idea how to acheive this answer?
     
  2. jcsd
  3. Sep 9, 2009 #2
    [tex]s=\frac{d}{t}[/tex]
    Speed is km/h, not h/km.
     
  4. Sep 9, 2009 #3

    rl.bhat

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    Show your conversion of time to hour.
     
  5. Sep 9, 2009 #4
    3 h 53min 17 s >3.29805556 hours
     
  6. Sep 9, 2009 #5

    rl.bhat

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    Now v = d/t.
     
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