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Volume and surface area

5 videos
6 skills
Ever wonder how a painter knows how much paint to buy to cover the exterior of your house? Or how much water you'll need to fill up your aquarium? Let's explore the volume and surface area of 3D shapes, such as rectangular prisms, rectangular triangles, and nets of ployhedra. These are fancy names for common shapes which you encounter all the time. Common Core Standards: 6.G.A.2, 6.G.A.4

Volume of a rectangular prism: fractional dimensions

VIDEO 4:15 minutes
Think of a rectangular prism as a 3 dimensional rectangle. To find the volume of a rectangular prism let's start by finding the volume of a rectangle, and go from there. What do you think we do next??

Volume with fractions


Volume of a rectangular prism: fractional cubes

VIDEO 4:18 minutes
Another way of finding the volume of a rectangular prism involves dividing it into fractional cubes, finding the volume of one, and then multiplying that area by the number of cubes that fit into our rectangular prism. Watch this ...

Volume with unit cubes 2


Volume of a rectangular prism: word problem

VIDEO 6:22 minutes
This is a cool word problem that puts together what we're learning about finding the volume of rectangular prisms. Follow along with Sal closely...he does a great job explaining.

Nets of polyhedra

VIDEO 6:48 minutes
We know...."nets of polyhedra" sounds like the title of a bad sci-fi movie about man-eating, muti-headed fish. A polyhedron ("polyhedra" is plural) is nothing more than a 3 dimensional shape with flat surfaces and straight edges (think: ...

Nets of 3D figures


Finding surface area: nets of polyhedra

VIDEO 4:19 minutes
Now we shift our focus towards surface area (which is the sum of all the areas of all the shapes that cover the surface of the object). Let's apply it to the polyhedra net we learned about in the previous video. We'll walk you through it.

Surface area using nets

Use the net of a 3D figure to find its surface area.

Surface area

Find the surface area of 3D objects.