Ed Tech – Tutorial

Approximating Pi

Use the slider to increase the number of sides for the inscribed regular polygon. Since pi is defined as the ratio of circumference to diameter, we approximate pi by calculating the ration of the perimeter of the polygon to the diameter of the circumscribed circle. As the slider increases the number of sides the polygon fits the circle closer and closer, until the polygon itself is "circle-like". This worksheet approximates pi from below, so it generates a lower bound for pi.

Follow-up Questions:

(1) How would you generate an upper bound for pi?

(2) How can you use the lower bound and upper bound together to calculate an better approximation for pi?