SOLUTION: The third term of a geometric sequence is 32 and the fifth term is 512. What is the eighth term of the sequence?

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Question 330097: The third term of a geometric sequence is 32 and the fifth term is 512. What is the eighth term of the sequence?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
a%28n%29=ar%5E%28n-1%29
a%283%29=ar%5E3=32
a%285%29=ar%5E5=512
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Find r,
%28ar%5E5%29%2F%28ar%5E3%29=512%2F32
r%5E2=16
r=4
Find a,
ar%5E2=32
a%2816%29=32
a=2
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highlight%28a%28n%29=2%284%29%5E%28n-1%29%29
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a%288%29=2%284%5E%288-1%29%29
a%288%29=2%2816384%29
highlight%28a%288%29=32768%29