What is the sum to infinity of the geometric series ?

Answer and explanation

Correct answer: A. 16

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  1. Step 1: An infinite geometric series with first term and common ratio converges to the sum .
  2. Step 2: Determine the initial term and compute common ratio by dividing the second term by the first term.
  3. Step 3: Substitute into to evaluate the sum: .
Answer
16.
Why not the others: '12' sums only the first two terms () instead of the full infinite series; '16/3' uses instead of in the denominator (calculating ); '24' adds rather than subtracts the constant term in the final step in evaluating .

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