###### 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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# Arithmetic Series - Problem 12

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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The keys to being able to work with arithmetic number patterns are knowing what is the first number in the pattern, and what is the constantly added difference, d. From there, you can use the explicit formula to find any term in the list, and the arithmetic series formula to find any sum. If the terms are irrational, finding d may be tricky: write an equation where you have one known term plus d equals the next term, and solve for d.

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