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Geometric progressions

Find the common ratio of a geometric series which has 2nd term 6 and sum to infinity of 24.
Not a clue- any hints please
Original post by Lucofthewoods
Find the common ratio of a geometric series which has 2nd term 6 and sum to infinity of 24.
Not a clue- any hints please


u2=6=aru_2=6=ar

r=1ur=24=a1r\displaystyle \sum_{r=1}^{\infty} u _r = 24 =\frac{a}{1-r}

Now find a way to combine the two.

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