The first term of an arithmetic sequence is 5 and the common difference is 5. What is the 12th term?
Answer and explanation
Correct answer: B. 60
- Step 1: a_n = a_1 + (n - 1)d.
- Step 2: a_12 = 5 + 11 x 5 = 60.
Answer
60.
Why not the others: 65 uses n instead of n - 1; 55 uses n - 2; the second value treats the sequence as geometric.
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