###### 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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# Area and Perimeter of Circles - Concept

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 Greek letter pi is the mathematical constant for the number 3.1415...which is a non terminating, non-repeating decimal. An exact answer would leave the letter pi in it, but we often find a decimal approximation using the rounded value 3.14 The area for a circle is pi times the radius squared, and the circumference, which is like the perimeter of the circle, is either pi times the diameter or 2 pi times the radius.

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