Question

3+7+11+.......up to 40 terms

find the sum of the following
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Answer 1

Answer:

hi.

Step-by-step explanation:

here. .

a= 3, n=40, d=4

now sum of the terms is given by the formula.

Sn= n/2(2a+(n-1)d)

S40= 40/2(6+156)

S40=20×162

S40=3240

the sum of 40 terms is 3240

Answer 2

ATQ

a=3,d=4,n=40.

so ,

sum=n/2(2a+(n-1)d)

40/2(2×3+(40-1)4)

20(6+39×4)

20(6+156)

20×162

3240