Area of a Circle

Radius

100

The diameter of a circle is 10, the radius is...

What is 5.

200

The diameter is 100, the radius is...

What is 50

300

The diameter is 15, the radius is...

What is 7.5?

400

The diameter is 25, the radius is...

What is 12.5?

500

The diameter is 0.5, the radius is...

What is 0.25?

Diameter

100

The radius is 5, the diameter is...

What is 10?

200

The radius is 20, the diameter is...

What is 40?

300

The radius is 4.5, the diameter is...

What is 9?

400

The radius is 10.5, the diameter is...

What is 21?

500

The radius is 1.15, the diameter is...

What is 2.3?

Circumference

100

The circumference of a circle that has a diameter of 2 is...

What is 6.28?

200

The circumference of a circle that has a diameter of 4 is...

What is 12.56?

300

What is the circumference of a circle that has a radius of 5???

What is 31.4?

400

The circumference of a circle that has a radius of 4.5 is...

What is 28.26?

500

The circumference of a circle that has a diameter of 12.5 is...

What is 39.25?

Area

100

The area of a circle that has a radius of 5 is...

What is 78.5?

200

The area of a circle that has a radius of 10 is...

What is 314?

300

The area of a circle that has a radius of 9 is...

What is 254.34?

400

The area of a circle with a diameter of 10 is...

What is 78.5?

500

The area of a circle with a diameter of 100 is...

What is 7850?

Challenge

100

The distance all the way across a circle.

What is the diameter?

200

The distance half way across the circle.

What is the radius?

300

The distance around the outside of a circle.

What is the circumference?

400

The amount of space inside a circle.

What is the area?

500

How are perimeter and circumference similar?

They both measure the distance around the outside of something.