Circles, Circles, Circles!

Circle Terms

100

The distance from the center of a circle to the outside, also half of the diameter

What is radius

200

The length across a circle, also double the radius

What is the Diameter

300

The distance around the outside of the circle.

What is circumference?

400

The total amount of space inside of a circle

What is the area?

500

3.14 or 22/7

What is pi?

Finding Radius and Diameter

100

The Diameter of this circle is 5. Find radius

What is 2.5

200

The Radius is 12. Find diameter

What is 24

300

The diameter of this circle is 27. Find radius

What is 13.5

400

The Radius of this circle is 37. Find diameter.

What is 74

500

The circumference is 25.12. Find the diameter.

What is 8?

Finding Area (400/500 are challenge problems!)

100

The radius is 5. Find area

What is 78.5

200

The radius is 2.5. Find area

What is 19.625

300

The diameter is 15.7. Find area

What is 193.49

400

The circumference of this circle is 18.84. Find area

What is 28.26

500

Which show a proportional relationship:

a. diameter to circumference

b. diameter to area

c. both

What is a. diameter to circumference

Finding Circumference (500 is a challenge problem!)

100

The diameter is 10. find circumference

What is 31.4

200

The diameter is 13. Find circumference

What is 40.82

300

The radius is 25. Find circumference

What is 157

400

The radius is 45. Find circumference

What is 282.6

500

The area is 452.16

What is 75.36

Riddles

100

 I am an odd number. Take away a letter and I become even. What number am I?

Seven

200

What can’t talk but will reply when spoken to?

an echo

300

What has many keys but can’t open a single lock?

A piano

400

What goes up and down but doesn’t move?

Stairs

500

What has words, but never speaks?

a book