Question

Which term of the sequence –1, 3, 7, 11, ….. , is 95 ?

Answer 1

Clearly, the given sequence is an A.P.

We have,

a = first term = –1 and, d = Common difference = 4.

Let 95 be the n^th term of the given A.P. then,

a_n = 95

⇒ a + (n – 1) d = 95

⇒ – 1 + (n – 1) × 4 = 95

⇒ – 1 + 4n – 4 = 95 ⇒ 4n – 5 = 95

⇒ 4n = 100 ⇒ n = 25

Thus, 95 is 25^th term of the given sequence