## Question

`Which term of the series 5, 8, 11, 14, …. is 320`

`Which term of the series 5, 8, 11, 14, …. is 320`

A. 65^{th}

B. 107^{th}

C. 105^{th}

D. 106^{th}

**Answer: D. 106**^{th}

^{th}

**Solution:**

Clearly, 5 + 3 = 8, 8 + 3 = 11, 11 + 3 = 14, …

So, the series is an A.P. in which a = 5 and d = 3.

Let 320 be the nth term of the series.

Then, 320 = 5 + (n – 1) × 3

=> (n – 1) = 105

**=> n = 106.**

**Read more:**

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