What is the sum of the infinite series 10 + 20/3 + 40/9 + ... in which each term is 2/3 of the previous one?
Answer and explanation
Correct answer: C.
- Step 1: The ratio is 2/3, which is less than 1 in absolute value, so the sum exists.
- Step 2: S = a/(1 - q) = 10/(1 - 2/3) = 30.
Answer
.
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