1. Finding Circumference for 4 th and 5 th Grade By Andrea Klee

2. What Is Circumference Circumference is the distance all the way around a circle. The equation to find circumference is 2  r or  multiplied by the diameter of the circle.

3. Some Terms Defined  is said as pie, like the kind you eat – about 3.14 r is the radius of a circle – or half the distance across a circle d is the diameter of a circle – or the distance all the way across a circle – or two radii added together

4. How To Find Circumference If you have the radius: – Multiply the radius by 2 to get the diameter. – Multiply this answer by 3.14 (  ). If you have the diameter: – Multiply the diameter by 3.14 (  ).

5. Let’s Try A Problem Find the diameter or the radius. We are going to find the radius. What is the radius of this circle?

6. Problem Continued The radius is 5. Next, multiply the radius by 2 to get the diameter. Last, multiply the diameter by  or 3.14.

7. Problem Solved The circumference of the circle is 31.4.

8. Here’s Another Problem Find the circumference of this circle.

9. Solution The diameter is 6. Multiply the diameter by  (3.14). The Circumference is 18.84.