SOLUTION: Find the sum of the infinite geometric series -12 + 48/5 - 192/25 + ... here are the answer choices A) negative 40/3 B)negative 80/3 C) negative 20/3 D) negative 10/3

Algebra ->  Sequences-and-series -> SOLUTION: Find the sum of the infinite geometric series -12 + 48/5 - 192/25 + ... here are the answer choices A) negative 40/3 B)negative 80/3 C) negative 20/3 D) negative 10/3       Log On


   

Question 873553: Find the sum of the infinite geometric series
-12 + 48/5 - 192/25 + ...
here are the answer choices
A) negative 40/3
B)negative 80/3
C) negative 20/3
D) negative 10/3
thank you!
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
S=-12*(1 - (-4/5)^20)/(1 - (-4/5))=-6 2/3
S=t*(1 - r^n)/(1 - r)
r=-4/5
c) -20/3 is -6 2/3