Q1 of 69 Page 78

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

Sum of first five multiples of 3 is. . .

First five multiples of 3 are


3, 6, 9, 12, 15


First term a = 3


Second term t1 = 6


Third term t2 = 9


Common difference d = t2 – t1 = 9 – 6 = 3


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 S5






Thus, correct answer is (A)

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