Find the diameter and the radius of a circle with a circumference of 465 cm. Give the answer to the nearest centimetre. Use π = 3۰142 or the π button on a calculator.

The circumference of a circle is its outside edge, and is the same distance from the centre at every point along its length. This distance is called the radius.

After you make it all the way around, the program calculates the circumference and radius of your circle—and from that, the value of pi. You can see the code by clicking the pencil icon.

Calculate the circumference of the Earth using this equation: Circumference = 360 x distance between your city and the equator / angle of shadow that you measured What value do you get?

How an ancient Greek mathematician calculated the Earth's circumference. In the mid-20th century, we began launching satellites into space that would help us determine the exact circumference of ...