Which term of the sequence 7, 10, 13, ..... is 151 ?

Let the nth term = 151
Here, first term = a = 7
common difference = d = 3
∴ t_n = a + (n – 1) d
⇒ 151 = 7 + (n – 1) × 3
⇒ (n – 1) × 3 = 144

⇒ n – 1 =	144	= 48
	3

⇒ n = 49