Which term of the A.P. 1, 4, 7, 10, ....... is 88 ? 1. 28th 2. 30th 3. 32nd 4. 40th

Mathematics

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Given,

A.P. = 1, 4, 7, 10, …….

Here,

First term (a) = 1 and Common difference (d) = 4 - 1 = 3.

Let nth term of the A.P. be 88.

So,

⇒ a_n = 88

⇒ a + (n - 1)d = 88

⇒ 1 + 3(n - 1) = 88

⇒ 1 + 3n - 3 = 88

⇒ 3n - 2 = 88

⇒ 3n = 90

⇒ n = $\dfrac{90}{3}$ = 30.

Hence, Option 2 is the correct option.

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