Question

Which term of the sequence 4, 9 , 14, 19, …… is 124 ?

Answer 1

Clearly, the given sequence is an A.P. with first term a = 4 and common difference d = 5.

Let 124 be the n^th term of the given sequence. Then, a_n = 124

a + (n – 1) d = 124

⇒ 4 + (n – 1) × 5 = 124

⇒ n = 25

Hence, 25^th term of the given sequence is 124.