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Homework Help: Word problem dealing with rate. Solve for rate of variable.

  1. Aug 6, 2012 #1
    1. The problem statement, all variables and given/known data

    You run a small business making widgets. You have two employees. Employee A takes two times as long as employee B to make a widget. During each day, both employees working together will make 15 widgets, how many widgets get made by employee A each day?

    2. Relevant equations

    rate = area/time


    3. The attempt at a solution
    I know the answer is 5 but I don't understand why. Here is my attempt.

    A = 2*B<--- A takes twice the time of B
    B = B

    since I am suppose to be solving for A write in terms of A
    B = A/2

    so their rate together should be A + B = 15 widgets.

    A/2 + A/2 = 15


    and this is were I get stuck.
     
    Last edited: Aug 6, 2012
  2. jcsd
  3. Aug 6, 2012 #2

    dlgoff

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    What is A equal to?
     
  4. Aug 6, 2012 #3
    A is equal to 2B.
    I tries doing 2B + B = 15
    which is 5 but that is solving for B not A
     
  5. Aug 6, 2012 #4

    dlgoff

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    Well you know what A + B equals to. So A = ?
     
  6. Aug 6, 2012 #5
    A = 15 - b
     
  7. Aug 6, 2012 #6

    dlgoff

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    I guess we need A=1/2B (or B=2A) since were talking about how many widgets A can make compared to B.

    Sorry about that.
     
  8. Aug 6, 2012 #7
    But A takes longer than B it takes twice as long as B does so A would be 2*B right?
    not the other way around?
     
  9. Aug 6, 2012 #8

    dlgoff

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    No. A takes twice as long so only makes half as many widgets as B. You want widgets not time.
     
  10. Aug 6, 2012 #9
    okay I got it now! I made a stupid error Thank you!
     
  11. Aug 6, 2012 #10

    dlgoff

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    I made the same mistake. :redface:
     
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