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Homework Help: I need help with conversions

  1. Feb 22, 2012 #1
    Convert 17,660 ft/min to mi/hr, ft= feet, min=minutes, mi=miles, hr=hours
    I first divided 17,660 feet per minute by 5280 ft then divided that quantity by 60 minutes and got 0.06 miles per hour. What did I do wrong?
  2. jcsd
  3. Feb 22, 2012 #2


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    Staff: Mentor

    When doing unit conversions, I find it best to keep multiplying by "1". You did the first part of the conversion correctly:

    17,660 ft/min * (1 mile / 5280 ft) = 3.345 mile/min

    But in the second part, what form of "1" should you multiply by to get to mile/hr?

    EDIT -- Keep in mind that by multplying by "1", your goal is to cancel out like units on the top and bottom of the fraction...
  4. Feb 22, 2012 #3

    jim hardy

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    Science Advisor
    Gold Member

    always write it out before start keying into calculator.
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