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.

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.

How to Solve for Radius in Excel. The radius of a circle or a sphere is the distance between the center and the edge. The radius can be used to calculate a circle's diameter, area and circumference.

The vertical side of this rectangle is the radius of the circle and the length of the side is half of the circumference (so, 2π R). Yes, the area of this rectangle would be π R2.

To do this, start by cutting a 3-inch piece of string to serve as the radius of the circle. What’s the radius? It’s half the diameter. Okay, but what’s the diameter?

Imagine the square’s sides are of length 2, so its area is 4; the circle’s diameter is therefore 2, and its area is pi. The ratio between their areas is pi/4, or about 0.7854.

Now, 7.2 is 1/50 of a full circle, which means that the distance between that two cities is 1/50 of the Earth’s circumference. <br /><br />To get the size of the earth, he multiplied 5,000 ...