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Fraction solving

  1. Jul 22, 2010 #1
    No homework, just a problem I'm faced with at work. And being the granny I am, this is ages ago since I solved anything like this.


    x/36-x = 12/36-12 + 3.013/0.20(36-3.013)

    The solution to this is 17.6. The question is: how do I solve such equations for x? If I ignore the 36 on the left side and asume it's not a fraction it's no problem, but um.. this is too long ago.
     
  2. jcsd
  3. Jul 22, 2010 #2
    Is the left hand side [tex] \frac{x}{36-x}[/tex] or [tex]\frac{x}{36} - x[/tex] ? I'm not sure where the fraction ends.
    In the first case multiplying both sides by [tex] 36-x[/tex] will get you rid of the fraction, in the second case multiply with 36. Then you can use addition and subtraction to solve for x.

    But no matter how i put the parenthesis in your equation i do not get the solution 17.6.
     
  4. Jul 22, 2010 #3
    first add all like term like the one whit out the x, then isolate for x, then you will have the answer.
     
  5. Jul 22, 2010 #4

    Mark44

    Staff: Mentor

    What you have written is straightforward and unambiguous, but it might not mean what you intend. Writing fractional expressions as text on one line requires the use of parentheses for numerators or denominators that have multiple terms.

    For x/36 - x, did you mean (x/36) - x or x/(36 - x)?
    For 12/36 - 12 did you mean (12/36) - 12 or 12/(36 - 12)? The first is a negative number; the value of the second is 1/2.

    For 3.013/0.20(36-3.013), did you mean (3.013/0.20) * (36 - 3.013) or 3.013/(0.20 *(36 - 3.013))?
     
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