Another Math problem

Discussion in 'General Discussions' started by domini212, Sep 24, 2008.

  1. domini212

    domini212 Level III

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    How do I put this into 2 equations. I have 6 more $5 bills than $10 bills. In total I have $225. If there are 39 bills in all how many $5 bills do I have.
    Let x represent the $5 bills and let y represent the $10 bills.
     
  2. mjnskivt

    mjnskivt Level III

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    I don't think you can have 39 bills and have 6 more 5s than 10s. If you have 22 5s and 16 10s you have 38 total, and if you have 23 5s and 17 10s you have 40 total.
     
  3. Nyamavu

    Nyamavu Level I

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    I don't know how to solve that one. I can come up with a few equations, but none of them work. I dont really understand the purpose of "y" unless you are trying to solve for it and you need to solve for "x" to get the answer. I also don't understand why there should be two equations.
     
  4. SoC

    SoC Moderator
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    X=5
    Y=10
    N= Amount of notes

    N x Y + (N+6) x X = 225
    10N+5(N+6)=225
    10N+5N+30 =225
    15N = 195
    N = 13

    This question is infact impossible to solve, its possible with 32 bills?
    Check that isn't a typo?
     
  5. Nyamavu

    Nyamavu Level I

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    In your equation you were trying to solve for the value of the bill. :x I did that too when I first tried it. When in doubt, write undefined! XD
     
  6. Dusk412

    Dusk412 Level I

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    How do I put this into 2 equations. I have 6 more $5 bills than $10 bills. In total I have $225. If there are 39 bills in all how many $5 bills do I have.
    Let x represent the $5 bills and let y represent the $10 bills.

    x = y + 6

    This is because if you have say 3 $10 bills, you will have 3+6 or 9 $5 bills. Which satisfies the first statement.

    5x + 10y = 225

    This is because each $5 bill is worth 5 and each $10 bill is worth 10, so the total amount of money would be 225, satisfying statement two.

    There is a third equation, because of statement three.

    x + y = 39

    Now there are two basic ways to solve this, substitution and combination. Unfortunately I have tried solving it and it does not work. Check with your teacher to see if there is a typo or poor instructions or something.
     
  7. fauxyx

    fauxyx Level I

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    N=13. I dont put anything in equations. I just do it. lol