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# Infinite Geometric Progressions Question watch

1. 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.
2. (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.
3. (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
4. (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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