SOLUTION: What is Sn for the arithmetic series with d = -4, an = 27, and n = 9? a. 360 b. 387 c. 418 d. 451

Algebra ->  Sequences-and-series -> SOLUTION: What is Sn for the arithmetic series with d = -4, an = 27, and n = 9? a. 360 b. 387 c. 418 d. 451      Log On


   

Question 294403: What is Sn for the arithmetic series with d = -4, an = 27, and n = 9?
a. 360
b. 387
c. 418
d. 451
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Sum=9%28a1%2Ba9%29%2F2
a9=27
a1=27%2B8%2A4=27%2B32=59
Sum=9%2859%2B27%29%2F2=9%2886%29%2F2=387
b) is the answer.