SOLUTION: what is the 8th term of 64,16,4,1

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Question 1087534: what is the 8th term of 64,16,4,1
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
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64,16,4,1 is a Geometric Sequence
a%5B1%5D=64 - the first term
r=a%5B2%5D%2Fa%5B1%5D=16%2F64=1%2F4 - the common ratio
a%5Bn%5D=a%5B1%5D%2Ar%5E%28n-1%29
a%5B8%5D=a%5B1%5D%2Ar%5E7
a%5B8%5D=64%2A%281%2F4%29%5E7=1%2F256
Answer: 1%2F256