A geometric sequence has first term 3 and common ratio 3. Find the sum of the first 7 terms.
Answer and explanation
Correct answer: B. 3279
- Step 1: .
- Step 2: .
Answer
3279.
Why not the others: 6561: that is the th term. 6558: it forgets to divide by . 2187: that is the last term.
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