Volume of pyramids and cones May 07, 2010
Volumes
of Pyramids and Cones
Objective
Find the volumes of
pyramids and cones.
Oct 2­5:03 PM
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Volume of pyramids and cones May 07, 2010
Cones are very similar to cylinders.
What differences do you see?
Pyramids are very similar to prisms.
Oct 2­5:17 PM
2
Volume of pyramids and cones May 07, 2010
How are prisms and pyramids with congruent bases and height related?
How many pyramids...
...will fit into one prism?
Oct 2­6:01 PM
3
Volume of pyramids and cones May 07, 2010
Pause for teacher
demonstration.
Oct 2­6:18 PM
4
Volume of pyramids and cones May 07, 2010
So, the volume of a prism is 3 times as big as the
volume of a pyramid with a congruent base and height.
In a formula, it looks like this:
Volume of prism = A h
base
Volume of pyramid = A h
base
3
Oct 2­6:24 PM
5
Volume of pyramids and cones May 07, 2010
Find the volume of this pyramid:
Step 1: Start with the formula
3.3 in.
V = A h base
3
6.2 in.
Step 2: Plug in the numbers
V = (6.2)(6.2) (3.3)
3
V = 42.284 cubic inches
Oct 2­6:30 PM
6
Volume of pyramids and cones May 07, 2010
Try a cone!
Step 1: Start with the formula
Step 2: Plug in the numbers
6 cm
4 cm
Oct 2­6:38 PM
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Volume of pyramids and cones May 07, 2010
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& Cones wkst
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