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Simple Alg 2 Help Needed on Interest

  1. Dec 9, 2008 #1
    1. The problem statement, all variables and given/known data

    Marianne borrowed 10000. She borrows from a friend at 8%, twice that amount from her bank at 9% and the rest from her Insurance at 5%. She pays a total of 830 in interest for the first year. How much did she borrow from EACH SOURCE?!!

    2. Relevant equations


    3. The attempt at a solution

    I tried on paper but got wrong values when i tried to see how much interest was from each source :(
  2. jcsd
  3. Dec 9, 2008 #2


    Staff: Mentor

    Show us what you tried.

    And for the interest rates, what period are they over? And what sorts of things did she borrow 10000 of?
  4. Dec 9, 2008 #3


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    Homework Helper

    Assume that she borrows 'x' amount from a friend, '2x' amount from her bank and rest from her insurance. Calculate interest paid for each amount for one year. Add it and equate it to 830. Solve for 'x'.
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