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Infinite Geometric Progressions Question Watch

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    Find the common ratio of a geometric series which has a 2nd term of 6 and a sum to infinity of 24.


    I know I have to use a/1-r.
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    (Original post by SuperSNESLiam)
    Find the common ratio of a geometric series which has a 2nd term of 6 and a sum to infinity of 24.


    I know I have to use a/1-r.
    for what im writing just let sum to infinty =§

    so, §=24, 24=a/1-r
    and, ar = 6

    you could make a=24(1-r) then substitue this into ar = 6 or just make a =6/r then substitute this into the § equation.
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    (Original post by SuperSNESLiam)
    Find the common ratio of a geometric series which has a 2nd term of 6 and a sum to infinity of 24.


    I know I have to use a/1-r.
    Good, use it

    Also use the other piece of info given in the question
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    (Original post by Bthrel12)
    for what im writing just let sum to infinty =§

    so, §=24, 24=a/1-r
    and, ar = 6

    you could make a=24(1-r) then substitue this into ar = 6 or just make a =6/r then substitute this into the § equation.
    Thanks!
 
 
 
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