Multiple choice

A sequence is defined by a1 = 4 and an = an-1 + 6, where n > 1. What is the fifth term in the sequence?

  1. 22

  2. 24

  3. 28

  4. 30
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The given sequence is an arithmetic progression where the first term is 4 and each subsequent term is obtained by adding 6 to the previous term. Calculating the terms step-by-step: a_1 = 4, a_2 = 10, a_3 = 16, a_4 = 22, and a_5 = 28.

AI explanation

This sequence follows a recursive formula where each term is found by adding 6 to the previous term, beginning with a1 = 4. To find the fifth term without finding all intermediate terms, use the arithmetic sequence formula an = a1 + (n - 1)d. Plugging in the values gives a5 = 4 + (5 - 1) * 6 = 4 + 24 = 28.

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