1. Wild about PI! Presenters: Tammy Bell -- Region VI LINCS Coordinator Tammy Cole -- Region VII LINCS Coordinator

2. This is a circle.

3. Radius This is the radius of a circle. It is a line segment starting from the center of the circle. The radius of this circle is four inches. 4 in.

4. Diameter To find the length across the circle you would double the radius. 4 in. 4 in The line segment that forms across is called the diameter . DIAMETER 4 in + 4 in = 8 in

5. Circumference To find the measurement all around the circle you would multiply the diameter by 3.14 or 3 for a good estimate!! Let’s Try!------------------->

6. Measuring Around the Circle Remember the radius is 4 inches . Double it to find the diameter . 4 in + 4 in =8 in The best estimate of the length around the circle is 24 inches. 8 in x 3 in = 24 in 4 in 8 inches

7. Measuring Circles Review Radius Diameter Circumference Measurement ALL around the circle.

8. Find the diameter: 5 in . 3 in 7 in. 10 inches 6 inches 14 inches

9. Find the Circumference Length around the circle. 5 in . 3 in 7 in. 30 inches 18 inches 42 inches

10. . . Great Job!