SOLUTION: Find the sum indicated for each of the geometric series listed 3 + 1.5 + 0.75 + ..., find S6

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Question 412049: Find the sum indicated for each of the geometric series listed
3 + 1.5 + 0.75 + ..., find S6
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Geometric Series: {3,1.5, 0.75 ...} r = .5  

sum%28+a%5Bi%5D%2C+i=1%2C+6+%29 = a(1-r^6)/(1-r)

sum%28+a%5Bi%5D%2C+i=1%2C+6+%29 = 3(1-.5^6)/.5 = 3*.984375/.5 = 5.90625



Note:

|r|<1 sum%28+a%5Bi%5D%2C+i=1%2C+infinity+%29 = a/(1-.5)=3/.5 = 6