A geometric series has sum to infinity and second term . What is the largest possible value of the first term?

Answer and explanation

Correct answer: B. 36

  1. Step 1: Set up equations with first term and common ratio (): , and second term .
  2. Step 2: Substitute into the sum to infinity: . Divide by : , giving or .
  3. Step 3: Compute corresponding values of : if , ; if , . The largest possible first term is .
Answer
36.

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