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  • Oct 4, 2009, 08:34 PM
    Rathviriya
    Mathematic Grade 11
    Given a,b,c,d,e as the progression of arithmetic.Calculate a,b,c,d,e by a+b+c+d+e=125 and a+b=38.
  • Oct 4, 2009, 09:40 PM
    Clough
    Hi, Rathviriya!

    If you post what you think the answer is and how you arrived at it, you'll be more likely to have someone come along who is knowledgeable to confirm whether your answer is correct, and if it isn't correct, to teach you how you might come up with the correct answer yourself.

    Thanks!
  • Oct 5, 2009, 11:54 PM
    Unknown008
    Hint: use the sum formula for arithmetic progression:



    Sn being the sum of the first n terms.

    So, that brings it to:



    And

    The formula for the nth term is

    For the first term, this is 'a'.
    The second term, b, it is : where the 'd' here is the common difference.
    The fifth term, e, is :

    Back the equations:


    |
    V



    |
    V


    with those two, you can solve simultaneously, and find the common difference d and the first term a. With those, the rest is easy!
    Hope it helped! :)
  • Oct 6, 2009, 12:45 AM
    Clough
    Hi again, Rathviriya!

    Now, you've been given the advice and help of Unknown008, who is an Expert at these sort of things.

    What do you think, please?

    Thanks!
  • Oct 9, 2009, 04:30 AM
    mathwiz3502
    Or, you could find two numbers that add up to 38, but they also have to have a difference that when added to the bigger number, it would equal 25 or the mean of a, b, c, d, and e.

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