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Surface Area and Volume

By Tomi Chen

Surface Area

Surface Area is the combined area of the outside of a 3D object. For shapes with edges, this may be as easy as adding together the area of all the faces, or may require complicated formulas.

Finding the surface area is helpful in the real world by, um, I don't really know. Gift wrap? With that you should be using more than just the surface area. Um, what about paint? You could just paint it, but maybe for large objects you want to know how much paint you need? Who knows? I'm just rambling so it looks like I have a lot written. This may not be very useful. Being able to find surface area is an important skill you need to have.


Volume is the amount of space inside a 3D object, or the amount of space a 3D object takes up. Finding volume can be as easy as just multiplying some numbers, or using some complicated formula which basically just multiplies numbers. Or, if it's an irregular object and you have it in real life, you could just throw it into some water. Remember: floating objects displace their weight in water, but sinking ones displace their volume. Also, one mL is equivalent to 1 cubic centimeter, and one mL of water is 1 gram.

Finding volume, in my opinion, is much more helpful and has many more real-world applications. For example, you may want to know the volume of your backpack to see how much it can hold. Maybe you want to know the volume of your water bottle. Maybe you want to know the volume of a fish tank. The point is, volume is much more useful than surface area. In my opinion.

Enough with the intro.
Let's get going!