Use the following formulae to work out the volumes of these shapes:
Cube
We must know the side length.
Remember that the length, the width and the height will all be equal to the side length because this is a CUBE.
Volume of cube = side length × side length × side length
Cuboid
We must know the length, the width and the height.
Volume of cuboid = length × width × height
e.g. Calculate the volume of this cuboid in cm3.
Answer:
The length is 15 cm, the width is 4 cm and the height is 8 cm.
Volume of cuboid = length × width × height = 15 × 4 × 8 = 60 × 8 = 480 cm3
e.g. Calculate the volume of this cube in mm3.
Answer:
The side length is 7 cm, so the width and the height are also 7 cm.
This will be 70 mm.
NB: We want the answer in mm3 which is why we should work in mm not cm. You must convert to the correct unit before doing the calculation. If you try to convert the answer, you will get it wrong!
Volume of cube = side length × side length × side length = 70 × 70 × 70 = 49 × 7 × 10 × 10 × 10 = 343 × 1,000 = 343,000 mm3
NB: The length, the width and the height are all interchangeable with each other, depending on how you look at a cuboid.
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