The first term of an arithmetic sequence is 5 and the common difference is 2. What is the 12th term?
Answer and explanation
Correct answer: B. 27
- Step 1: a_n = a_1 + (n - 1)d.
- Step 2: a_12 = 5 + 11 x 2 = 27.
Answer
27.
Why not the others: 29 uses n instead of n - 1; 25 uses n - 2; the second value treats the sequence as geometric.
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