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the fifth term of a geometric system is 112 and the ninth term is 1792. find the common ratio of the sequence

User Jsosnowski
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1 Answer

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We can find the common ratio by setting up a ratio :P of the two given points...

Since any geometric sequence term is a(n)=ar^(n-1) and we have two terms we can say:

1792/112=(ar^8)/(ar^4)

16=r^4

r^2=4

r=2

So the common ratio is 2.
User Chris Lees
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