alleryThe sum to infinity of the series $1 + \tfrac{1}{3} + \tfrac{1}{9} + \cdots$ is:
A$3$
B$\tfrac{9}{8}$
C$\tfrac{3}{2}$
D$2$
Answer & Solution
Correct answer: C. $\tfrac{3}{2}$
Infinite G.P. sum = a/(1−r) = 1/(1−⅓) = 1/(⅔) = 3/2.
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