What are Some Example Problems of Pie?

Circumference of a Circle
You can find the circumference of a circle by multiplying Pi by the diameter of the circle.
If a circles' diameter is 4, then to find the circumference you would multiply 4 X 3.14.
If you have the radius and not the diameter then double the radius to get the diameter and multiply that by 3.14

Surface Area of a cylinder
To find the surface area of a cylinder you would  multiply Pi times the radius squared times two (since there is a top and bottom) and then add pi times the radius and then multiply by two and times by the height of the cylinder.
2(pi r 2) + (2 pi r)* h  would be the formula.

The Area of a Sector of a Circle
To find the area of a sector of a circle you would take the number of degrees that the sector covers and then divide it by 360 in order to get the fraction of the circle that the sector covers. Then you would multiply that by pi times radius squared.

Real life Application of Pi
A real life application problem that uses this problem would be a farmer that needs to know the amount of corn he would be able to put in his silo. He could find this by finding the volume of the silo by using the volume of a cylinder formula which is pi X radius squared X height.
V=pi r2 h would be the formula.