Pyramid: Volume
How to find the volume of a pyramid: formula, 2 examples, and their solutions.
Formula
V = [1/3]Bh
V: Volume of a cone
B: Base area
h: Height
The pyramid doesn't have to be
a regular pyramid.
Example
Find the base area B.
The base is a rectangle.
Its sides are 7 and 4.
So the area of the rectangle is
B = 7⋅4.
7⋅4 = 28.
So the base area B is 28.
The height h is 9.
B = 28
h = 9
Then the volume V
is equal to
1/3
times,
the base area, 28
times,
the height h, 9.
[1/3]⋅9 = 3
28⋅3 = 84
So the volume of the pyramid is 84.
Example
Find the base area B.
The base is a right triangle.
Its legs are 8 and 9.
So the area of the triangle is
B = [1/2]⋅8⋅9.
You can also choose the other triangles
as the base.
You'll get the same answer.
[1/2]⋅8 = 4
4⋅9 = 36
So the base area B is 36.
The height h is 10.
B = 36
h = 10
Then the volume V
is equal to
1/3
times,
the base area, 36
times,
the height h, 10.
[1/3]⋅36 = 12
12⋅10 = 120
So the volume of the pyramid is 120.