Parts of the Circle: Calculating the size

Look at the circle below.

The length of segment MO is equal to 6 cm.

What is the size of the diameter of the circle?

$12$

M is the center of the larger circle.

O is the center of the smaller circle.

Point A is the starting point of both circles.

$AO=3$

$MA=6$

How long is line segment BC?

$BC=18$

M is the center of the green circle.

O is the center of the red circle.

The length of the diameter of the red circle is 8 cm.

What is the size of the radius of the red circle?

$OB=4$

Look at the circle below.

The length of the line segment MO is 6 cm.

How long is the radius?

$6$

Look at the circle below.

MO is 6 cm long.

How long is AB?

$12$

M is the center of the larger circle.

O is the center of the smaller circle.

A is the starting point of both circles.

$MA=6$

How long is the diameter of the larger circle?

$AB=12$

M is the center of the green circle.

O is the center of the red circle.

The length of the diameter of the red circle is 8 cm.

What is the diameter of the green circle?

$AB=16$

A is the center of the black circle.

$AB=5$

What is the diameter of the black circle?

$10$

A is the center of the black circle.

$AB=5$

What is the diameter of the green circle?

$5$

A is the center of the black circle.

$AB=5$

What is the radius of the red circle?

$2\frac{1}{2}$