In an arithmetic sequence the third term is 11 and the seventh term is 23. What is the 12th term?
Answer and explanation
Correct answer: C. 38
- Step 1: Seventh term - third term = 4d, so 4d = 23 - 11 = 12 and d = 3. Step 2. First term a = 11 - 2 x 3 = 5. Step 3. a_12 = 5 + 11 x 3 = 38. Answer: 38. Why not the others: 41: That is the next term, the 13th. 35: That is the previous term, the 11th. 20: That adds 1 for each step instead of the common difference.
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