alleryThe sum of the first 5 terms of the G.P. 1, 2/3, 4/9, 8/27, … is:
A211/81
B81/211
C211/243
D243/211
Answer & Solution
Correct answer: A. 211/81
We have S_5 = 3(1 − (2/3)^5).
That is S_5 = 3·(211/243).
So S_5 = 211/81.
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