Find the 15th term of the arithmetic progression with first term a_1 = 4 and common difference d = 3.5.
Answer and explanation
Correct answer: C. 53
- Step 1: Use the nth term formula: a_n = a_1 + (n - 1)d. Step 2. For n = 15: a_15 = 4 + (15 - 1)(3.5) = 4 + 14 3.5 = 4 + 49 = 53. Answer: 53. Why not the others:* 56.5 mistakenly uses n instead of (n - 1); 49.5 and 52.5 result from multiplication errors.
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