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Simple 4th grade question I presume

  1. Mar 20, 2007 #1
    Does anyone know (I know I should) how to find the value of two masses when you have:

    the ratio of masses (m1/m2)


    the sum of the masses (m1 + m2)

    m1/m2 = 0.7941

    m1+m2 = 13 kg

    My first thought was m1/m2 * m1 + m2 = 10.3233 = m2

    Clearly not right though as the ratio of m1 to that is not the ratio I found.
  2. jcsd
  3. Mar 20, 2007 #2


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    Homework Helper

    From your ratio you can say m1=0.7941*m2.
  4. Mar 20, 2007 #3
    You have 2 equations and 2 unknowns. Pick one equation and solve for one of the variables. Then plug this into the second equation so that you have everything in terms of the one variable. Then you can solve for it and plug into the original equation to find the second unknown. If youre in 4th grade, get used to this, because youll come across it a lot
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