What is the sum to infinity of the geometric series 8 + 4 + 2 + ...?
Answer and explanation
Correct answer: C. 16, from a/(1 − r)
- Step 1: The first term is 8 and the ratio is 1/2. Step 2. S = a/(1 − r) = 8/(1/2) = 16. Answer: 16. Why not the others: 14 sums only three terms, 12 uses ratio 1/3 and 32 divides by r wrongly.
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