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Homework Help: Calculate average mph

  1. Jun 2, 2010 #1
    1. The problem statement, all variables and given/known data

    A person travels at a constant speed of 66 miles per hour for 30 minutes, 27 miles per hour for 45 minutes, and stops for lunch for 20 minutes. Calculate the average speed for the entire trip (in miles per hour).

    2. Relevant equations

    3. The attempt at a solution
    66mph for 30mins= 33miles, 27mph for 4min= 20.25miles, and 0mph for 20min= 0miles

    33+20.25+0= 53.25miles

    What do I do after I have found this information?
  2. jcsd
  3. Jun 2, 2010 #2
    Find the total travel time and divide.
  4. Jun 2, 2010 #3
    95min/53.25= 1.78mph... that seems to slow
  5. Jun 2, 2010 #4
    What units was the time in the denominator expressed in?
  6. Jun 2, 2010 #5
    divide 95 by 60 to get the answer in hours...

    53.25miles/1.58hrs= 33.64mph
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