SOLUTION: Find the sum of the infinite geometric series, if possible. 120 + 60 + 30 + . . .

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Question 387761: Find the sum of the infinite geometric series, if possible.
120 + 60 + 30 + . . .
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Recall that the sum (S) of an infinite geometric series with first term, a%5B1%5D, and common ratio, r,is given by:
S+=+a%5B1%5D%2F%281-r%29 Here, a%5B1%5D+=+120 and r+=+1%2F2 so...
S+=+120%2F%281-1%2F2%29
S+=+120%2F%281%2F2%29
S+=+120%2A2
S+=+240