SOLUTION: In a certain sequence, each term is equal to (3) times the pervious term. If the fifth term in the sequence is 27, what was the first term?

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Question 379877: In a certain sequence, each term is equal to
(3)
times the pervious term. If the fifth term in
the sequence is 27, what was the first term?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,

this is an example of a Geometric Sequence, where the common raio is 3

For a Geometric Sequence a%5Bn%5D+=+a%5B1%5D%2Ar%5E%28n-1%29

Question States

a%5B5%5D+=+a%5B1%5D%2A3%5E%285-1%29=27

a%5B1%5D%2A3%5E%284%29=27

a%5B1%5D=27%2F81+=+1%2F3



CHECKING our answer by reviewing the first 5 terms of this sequence:

 1/3, 1, 3, 9, 27