For the sequence a_n = 3n + 2, what is a_5?

For the sequence a_n = 3n + 2, what is a_5?

• A. 11
• B. 14
• C. 17
• D. 20

Answer: (C)

In this kind of question, you read the formula as a direct rule for any position in the sequence. To find the fifth term, substitute n = 5 into a_n = 3n + 2. That gives a_5 = 3(5) + 2 = 15 + 2 = 17. So the fifth term is 17. This matches the pattern since each step adds 3 to the previous term (a_1 = 5, a_2 = 8, a_3 = 11, a_4 = 14, a_5 = 17). The other numbers shown (11, 14, 20) correspond to other indices, not the fifth term.

In this kind of question, you read the formula as a direct rule for any position in the sequence. To find the fifth term, substitute n = 5 into a_n = 3n + 2. That gives a_5 = 3(5) + 2 = 15 + 2 = 17. So the fifth term is 17. This matches the pattern since each step adds 3 to the previous term (a_1 = 5, a_2 = 8, a_3 = 11, a_4 = 14, a_5 = 17). The other numbers shown (11, 14, 20) correspond to other indices, not the fifth term.