Volume is the amount of space inside a 3-dimensional figure. It is measured in cubic units. A cubic centimeter is a cube that is 1 cm wide, 1 cm long, and 1 cm high.

You are watching: How many cubes are in a rectangular prism

Another way to think of volume is to find the number of unit cubes necessary for building the figure.

 Example 1Suppose this is a cubic unit: How many cubic units would be needed to build this object? Example 2How many unit cubes are needed to build this object? Example 3How many cubes are in this figure? There are 6 cubes on the bottom "floor" There are also 6 cubes on the second "floor" And there are 6 cubes on the third (top) "floor"So, there are 18 cubes in this figure.

Example 3 shows us that a shortcut for finding the volume of a rectangular prism is to find the number of cubes on the bottom "floor" and the multiply by the number of floors.

 Volume = (number of cubes on the bottom floor) x (number of floors) Volume = Area of the base x height Volume = l • w • h

Let"s practice this shortcut with a few more examples...

 Example 4Find the volume of this rectangular prism. Volume = (Area of the base) • (height) Volume = (4 • 3) • 5 Volume = 60 \$mboxcm^3\$(If you look at each layer, there are 12 cubes in each. There are 5 layers, so that would make a total of 60 cubes.)

 Example 5Find the volume. Volume = l • w • hVolume = 6 • 3 • 3Volume = 36 cubic units

 Example 6Find the volume. V = l • w • hV = 5 • 4 • 7V = 140 units cubed

Self-Check
 Question 1Find the volume of this prism. \$large~24mbox u^3\$
 Question 2Find the volume.See more: Does My 2007 Kia Optima Timing Belt Or Chain ? Does A Kia Optima Have A Timing Belt \$large~42mbox cm^3\$

Question 3

Find the volume. \$large~48mbox cm^3\$

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