Q1 of 69 Page 78

Choose the correct alternative answer for each of the following sub questions.

What is the sum of the first 30 natural numbers ?

List of first 30 natural number is


1, 2, 3,……..,30


First term a = 1


Second term t1 = 2


Third term t2 = 3


Common difference d = t3 – t2 = 3 – 2 = 1


number of terms n = 30


Thus, By using sum of nth term of an A.P. we will find it’s sum



Where, n = no. of terms


a = first term


d = common difference


Sn = sum of n terms


We need to find S30



⇒ S30 = 15 [ 2 + 29]


⇒ S30 = 15 × 31


⇒ S30 = 465


Hence, Correct answer is (B)

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