###### Alissa Fong

MA, Stanford University
Teaching in the San Francisco Bay Area

Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts

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# Geometric Series - Problem 13

Alissa Fong
###### Alissa Fong

MA, Stanford University
Teaching in the San Francisco Bay Area

Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts

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In order to find a finite sum of a geometric sequence, (that is, a list of numbers where there is a common "multiply by number," or r), you will need three pieces of information: the first term, the ratio, and how many terms are being added. From there, plug those values into the formula for a geometric series and evaluate, being especially careful with the order of operations. Simplify what is inside the parentheses, then do the exponent, and then multiply by the term out front.

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