1. Review: Perimeter & Circumference
Math 8

2. Brainstorm
Paul wants to make a sandbox out of logs. How can he figure out how many logs he needs?

3. Perimeter "peri" - around, "meter" - measure
The distance around a figure. 
To find the perimeter = ADD UP ALL THE LENGTHS OF ALL THE SIDES. 

4. Estimate then calculate the perimeter of the garden

5. Calculate the perimeter

6. Calculate the perimeter

7. Calculate the perimeter

8. Circumference C = πd C = 2πr π= 3.14
Is the distance (perimeter) around a circle. 
Formula:
C = πd
C = 2πr
π= 3.14

9. The diameter of a Ferris Wheel is 55m. What is the circumference?
C = πd
         = 3.14 x 55m
         = 172.7mm

10. The radius of a pizza is 3. 5inches
The radius of a pizza is 3.5inches. What is the circumference of the pizza?
C = 2πr
         = 2 x 3.14 x 3.5
         = inches 

11. Practice Complete: Perimeter – Mathpower 8
Circumference of a Circle – Mathpower 8
Perimeter & Circumference