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Need equation created

  1. Sep 22, 2006 #1
    I can't figure this one out. It sounds simple but I can't get anything to work.

    If a computer costs 300-399 charge 2.00 handling charge.
    If a computer costs 400-499 charge 2.50 handling charge.
    If a computer costs 500-599 charge 3.00 handling charge.

    So for every hundred add $.50.

    $1-$100 add .50
    $101-$200 add 1.00
    $201-$299 add 1.50

    So part of the equation could be 2.00+.5x this part will work if I can get x to equal 1,2,3.

    As you can see I am completely confused on how to do this. Any help will be appreciated.
  2. jcsd
  3. Sep 22, 2006 #2
    First of all, you should decide what y and x should be. Y is dependant of what x is. Is y the handling charge or the total price? What will x be in that case?
  4. Sep 22, 2006 #3


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    Staff Emeritus
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    Gold Member

    The "equation" for this is actually going to be discontinuous. When x goes from 399 to 400, y jumps from 2.00 to 2.50.

    These kinds of equations cannot be cast in the form y = ax + b, because of those discontinuities.

    The best way to describe this relationship would be to use a piecewise function. Do you know what those are?

    - Warren
  5. Sep 22, 2006 #4
    I don't know what piecewise functions are. I will look up what they are and see if I can figure it out. Any pointers you could give would be very appreciated.
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