SOLUTION: 5 + 5/6 + 5/6^2 + 5/6^3+... find the sum of the infinite geometric equation

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Question 153919: 5 + 5/6 + 5/6^2 + 5/6^3+...
find the sum of the infinite geometric equation
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
5+%2B+5%2F6+%2B+5%2F6%5E2+%2B+5%2F6%5E3%2B... 

The formula is 

S%5Binfinity%5D+=+a%5B1%5D%2F%281-r%29,

where a%5B1%5D+=+FIRST_TERM+=+5

To find r, divide the second term a%5B2%5D or 5%2F6 
by the first term a%5B1%5D or 5:

r=5%2F6÷5 = 5%2F6÷5%2F1 = 5%2F6×1%2F5 = cross%285%29%2F6×1%2Fcross%285%29 = 1%2F6

Plug in:

S%5Binfinity%5D+=+a%5B1%5D%2F%281-r%29

S%5Binfinity%5D+=+5%2F%281-1%2F6%29

S%5Binfinity%5D+=+5%2F%286%2F6-1%2F6%29,

S%5Binfinity%5D+=+5%2F%285%2F6%29,

S%5Binfinity%5D+=+%285%2F1%29%2F%285%2F6%29,

S%5Binfinity%5D+=+5%2F1÷5%2F6

S%5Binfinity%5D+=+5%2F1×6%2F5

S%5Binfinity%5D+=+cross%285%29%2F1×6%2Fcross%285%29

S%5Binfinity%5D+=+6

Edwin