calculate s20 for the arithmetic sequence in which a11=3.2 and the common difference is d=2.9

A. -25.8
B. 35
C. 29.3
D. -87.6

4 answers

D. -87.6
AAAaannndd the bot gets it wrong yet again!

S20 = 20/2 (2*(3.2-10*2.9) + 19*2.9) = 35
the bot is never right lol who created that
The bot is just an insult to all of us.