6th Grade Math Textbook, Progress

Volume of Triangular Prisms and Cylinders

13-17

You can use the formula V
Bhwhere Bis

the base area and his the height, to find

the volume of triangular prisms and cylinders.

Find the volume of the triangular prism

at the right.

To find the volume of a triangular prism:

Find the area of the triangular

base, B.

Multiply the area of the base, B,

by the height of the prism, h. The

product is the volume, V.

The volume of the triangular prism is 100 in.^3.

Find the volume of a cylinder that has a

radius of 2 in. and a height of 8 in.

To find the volume of a cylinder:

Volume of a Triangular Prism

V
Bh
(

1

2

bh) h

Find the area of the circular base, B.

Multiply the area of the base, B, by

the height of the prism, h. The

product is the volume, V.

The volume of the cylinder is about 100.48 in.^3.

Volume of a Cylinder

V
Bh
(r^2 ) h

A
r^2


3.14 (2 in.)^2 
12.56 in.^2

V
Bh


12.56 in.^2 8 in. 
100.48 in.^3

B


1

2 bh



1

2 5 in.4 in.
10 in.

2

V
Bh


10 in.^2 10 in.
100 in.^3

10 in.

5 in. 4 in.

r 
 2 in.

h 
 8 in.

height of prism

base of triangle

height of

triangle

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