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Homework Help: Setting up linear equations for problems dealing with specific gravity.

  1. Sep 24, 2005 #1
    I can not, for the life of me, figure out how to set the following up into a system of equations.

    An object composed of x gram-mole of lead (specific gravity 11) and y gram-mole of tin(specific gravity 7) weights 82 gram-moles in air and 77 gram-moles in oil of specific gravity of 1/2. Find x and y.

    Finding x and y is simple, if I could figure out the right way to set it up...:(
     
  2. jcsd
  3. Sep 24, 2005 #2

    lightgrav

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    I would start with a statement of mass addition,
    and a statement of volume addition.
    The buoyant Force (5gram)g = V*(.5gram/cm^3)g
    gives you a way to write the total Volume.
     
  4. Sep 25, 2005 #3
    I still cant get it to come out to the correct answer...
     
  5. Sep 25, 2005 #4

    lightgrav

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    "correct answer" might be wrong.
    maybe youmade an algebra mistake...
    what have you done so far?
     
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