The first term of an arithmetic sequence is 5 and the common difference is -3. What is the 10th term?
Answer and explanation
Correct answer: C. -22
- Step 1: a_n = a_1 + (n - 1)d.
- Step 2: a_10 = 5 + 9 x -3 = -22.
Answer
-22.
Why not the others: -25 uses n instead of n - 1; -19 uses n - 2; the second value treats the sequence as geometric.
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