Answer:
The circumference of a circle is the length of the line around the edge of the circle. A circle's circumference, c, is equal to twice its radius, r, times π. This can be expressed as the following equation:
c = 2πr
Since π is 3.14, this can also be written as c = 6.28r
To calculate circumference, then, you multiply the circle's radius by 6.28. Take a circle with a radius of 4 inches. Multiplying the radius by 6.28 give you 25.12. So the circle's circumference is 25.12 inches.
You can calculate the area of a circle using the circle's radius. The area of a circle is equal to π times the radius squared. Remember that any number squared is equal to that number multiplied by itself. So area, A can be found using this equation:
A = πr^2 or A = π x r x r
For example if you're trying to calculate the area of a circle with a radius of 3 inches. You'd multiply 3 times 3 to get 9, and multiply 9 times π. Remember that π is equal to 3.14. Also note that when you multiply inches by inches, you get square inches, which is a measurement of area instead of length.
A = π x 3 ins x 3 ins A = 3.14 x 9 sq ins A = 28.26 sq ins
So the circle has an area of 28.26 square inches.
I did not copy and paste this, I hope it's helpful!
