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18 votes
18 votes
What is the correct formula to find the sum of the finite geometric series below?


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User Marcelo Boeira
by
2.7k points

2 Answers

24 votes
24 votes

Explanation:


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r =
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r =
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r =
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Soo :


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image


image

User Hoyen
by
2.5k points
24 votes
24 votes

We are given the Geometric Series:


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which can be rewritten as:


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here, we can see that every term is (1/3) times the last term

Hence, we can say that the common ratio of this Geometric Series is 1/3

Finding the Sum:

We know that the sum of a Geometric Series is:


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(where r is the common ratio, a is the first term, and n is the number of terms)

another look at the given Geometric Series tells us that the first term is 2 and the number of terms is 7

plugging these values in the formula, we get:


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Sₙ = 2.97

User Raygerrard
by
2.3k points