A Common Ratio

Compare the ratio of the circumference (C) and the diameter (d) of several circles.

Rationalize Pi

Approximate pi with a rational number.

N-Sided Circle?

Compare the perimeters of polygons to the circumference of a circle.

Wrapping Around the World

How much string is needed to wrap around the world?

Walking Around the World

Compare the distance a man’s head travels to the distance his feet travel when he walks around the world.

Surface Area

Relate the surface area of a sphere to the area of a circle.

Surrounding Squares

Find a method that will construct a square that has the same area as the area of a given circle.

Circle Inscribed in a Semicircle

Compare attributes of a circle that is inscribed in a semicircle to attributes of that semicircle.

Segment Areas

Determine the measure of the central angle of a circle that will make the shaded region’s area 1/ 4 of the entire circle’s area.

Dividing Pizza

Compare slices of pizza from pizzas with different diameters.