6th Grade Math Textbook, Progress

Volume of Pyramids

13-18

The volume of a pyramid is equal to one-third the volume

of a prism that has the same base and height.

The rectangular prism and the square pyramid below have congruent

bases and have the same height. Find the volume of each.

Volume of rectangular prism

V

w h


3 in.3 in.6 in.


54 in.^3

Volume of square pyramid

V
^13 
w h

^13 (3 in.3 in.6 in.)

^13 (54 in.^3 )
18 in.^3

The volume of a pyramid is one third

the product of the area of the

base and the height of the pyramid.

Study these examples.

V
^13 Bh

^13 (8 cm)^2 6 cm

128 cm^3

V
^13 Bh

^13 (25 ft)^2 19 ft

 3958 ^13 ft^3

Volume of a Pyramid

V
^13 Bh

3 in.

3 in.

6 in. h^5 6 in.^

3 in.

3 in.

6 cm

8 cm

8 cm

25 ft

25 ft

19 ft

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