SOLUTION: For the geometric series: 8+2+1/2+1/8+... find S1,S2,S3,S4 and S5. I alread found that S1=8, S2=10, S3=10 1/2, but I need S4 and S5. I also need to use these sums to approximate

Algebra ->  Sequences-and-series -> SOLUTION: For the geometric series: 8+2+1/2+1/8+... find S1,S2,S3,S4 and S5. I alread found that S1=8, S2=10, S3=10 1/2, but I need S4 and S5. I also need to use these sums to approximate       Log On


   

Question 450317: For the geometric series:
8+2+1/2+1/8+...
find S1,S2,S3,S4 and S5. I alread found that S1=8, S2=10, S3=10 1/2, but I need S4 and S5. I also need to use these sums to approximate S. Then I need to use the Infinite Geometric Series formula, which is S=S1/r-1, to find S.
S1= 8, because its the first number in the series
R= the common ratio, which I don't know
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
S%5B4%5D+=+10%261%2F2+%2B+1%2F8+=+85%2F8
S%5B5%5D+=+85%2F8+%2B+1%2F32+=+341%2F32
The formula for the sum of an infinite geometric series is S+=+s%5B1%5D%2F%281-r%29, where -1 < r <1. Here r = 1/4. Hence S+=+8%2F%281-1%2F4%29+=+8%2F%283%2F4%29+=+32%2F3