Question

Find The sun of first 22 terms of an AP in which d=7 and 22nd term is 18

Answer 1

Answer:

The correct answer is –1221.

Explanation:

Working formula=(a+l)×n/2

where a= initial term,l= last term,n= total number of term

Now from the given condition

18=a+(22-1)×7

a=-129

The sum of first 22 terms of AP is

(-129+18)×22/2=(-1221)

PLEASE MARK AS BRAINLIEST ANSWER DON'T FORGET TO PRESS ON THANKS IF YOU FIND IT HELPFUL