Find the sum of the first seven terms of the sequence 4, 12, 36, 108, … .
1 answer:
The given sequence is 4,12,36,108....
Here we can observe the first term = 4 ,
and so on.
The common ratio (r)=
Since the common ratio is greater than 1,
Therefore the sum of the geometric series =
Since we have to find the sum of first seven terms, so n=7
=
=4372.
Therefore, option C is the correct answer.
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