Question

The button on David's coat has a radius of 4
millimeters. What is the button's diameter?

Answer 1

0.013

I think.

Explanation:

Answer 2

8

Explanation:

So there are two things that must be remembered.

The radius is half of the diamater. It is the distance from the side of a circle to its center.

The diamater is two times the radius. It is the distance from one side of the circle to the opposite side of the circle.

In this case, we know the radius is 4.

The radius is half of the diamamter, or the diamater is two times the radius.

This can be though of as:

2r=d

Or

1/2d=r

So lets plug 4 in for r:

2*4=d = 8=d

1/2d=4 = 2*1/2=4*2 = 1d=8

So using either of these formulas, we find d is equal to 8.

Hope this helps!