This is how you find the Surface Area of a Sphere. You can see in the picture above that there are four circles filed with Orang peels. Before the Orange peels we had a full Orang. We cut that Orang in half and traced it out on the paper. Then we broke apart the Orange peel and placed them in the circles that we drew. What this is saying is that the Surface Area of a Sphere (which is a 3D shape) can fit into four 2D circles. The Surface Area of a Circle is πrˆ2 so to find the Area a a Sphere your formula would be 4 x πrˆ2. For example the Diameter of the Orange when it was a full Sphere was 8.2 cm. To find the radius you just divide 8.2 by 2 which leaves you with 4.1 cm for the radius, then you just plug that into the equation.
SA= 4 x π x 4.1ˆ2=
SA= 4x π x 16.81=
SA= 211.24cmˆ2