An infinite geometric series has common ratio -1/3 and sum 25. What is the second term of the sequence?
I got it, but you can answer anyways.
We can find the first term a1, thusly
a1
____ = Sum .......so......
1 - (r)
_______ = 25
1 - (-1/3)
____ = 25 multiply both sides by 4/3
4/3
a1 = 25 (4/3) = 100/3
So.....the second term is (100/3) (-1/3) = -100 / 9
Thank you so much!
+654 
