Q34 of 84 Page 5

Find the sum of first 8 multiples of 3. (CBSE 2018)

To Find: Sum of first 8 multiples of 3

This means: 3 + 6 + 9 + ......+ (upto 8 multiples)

This sum can be found out using AP whose:

• First Term (a) = 3

• Common Difference (d) = 3

• Number of Terms (n) = 8

Formula Used:

where, n = number of terms, a = first term and d = common difference.

Putting the necessary values,

Required Sum

Required Sum = 108

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