Question

The sum of 40 terms of an ap whose first term is 2 and common difference 4 will be

Answer 1

Sn=(n/2)(2a+(n-1)d)=(40/2)(2*2+(40-1)4)=(20)(4+160-4)=20*160=3200, mark Brainliest answer

Answer 2

Answer:

3200

Step-by-step explanation:

Given :First term is 2 and common difference is 4

To Find : The sum of 40 terms

Solution:

First term = a = 2

Common difference = d = 4

Formula of sum of first n term = $S_n=\frac{n}{2}(2a+(n-1)d)$

Substitute n = 40

$S_{40}=\frac{40}{2}(2(2)+(40-1)4)$

$S_{40}=3200$

Hence the sum of first 40 terms is 3200