SOLUTION: The common ratio of a geometric series is 1/3 and the sum of the first 5 terms is 121. What is the value of the first term?

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Question 842381: The common ratio of a geometric series is 1/3 and the sum of the first 5 terms is 121. What is the value of the first term?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!

S=t*(1 - r^n)/(1 - r)
121=t*(1 - 1/3^5)/(1 - 1/3)
t1 = 81