RECTANGULAR PRISMS SURFACE AREA AND VOLUME NOTES
SURFACE AREA OF A RECTANGULAR PRISM Use the formula A = l w to find the area of
each face and add the areas together. A rectangular prism has 6 faces.
h = 1 in.
Example:
w = 2 in.
l = 4 in.
Face
Dimensions
l
l
l
l
w
w
Front
Back
Top
Bottom
Side
Side
x
x
x
x
x
x
h
h
w
w
h
h
Area
A = 4 in. x 1 in. = 4 in2
A = 4 in. x 1 in. = 4 in2
A = 4 in. x 2 in. = 8 in2
A = 4 in. x 2 in. = 8 in2
A = 2 in. x 1 in. = 2 in2
A = 2 in. x 1 in. = 2 in2
TOTAL SURFACE AREA = 28 square inches
It will take 28 of the 1 inch squares to cover this rectangular prism.
Or
Surface area =
2lw + 2lh + 2wh
2(4 x 2) + 2(4 x 1) + 2( 2 x 1)
16 in.2 + 8 in.2
+
4 in.2
Multiply:
Or
l x w = 8 in.2
l x h = 4 in.2
SHORTCUT
l
w
h
4
2
1
8
= 28 square inches
w x h = 2 in.2
14 in.2 + 14 in.2
= 28 in.2
2
Add your answers and double it for total surface area.
4
VOLUME OF A RECTANGULAR PRISM
h = 1 in
w = 2 in
l = 4 in.
How many 1 inch cubes will this rectangular prism hold?
volume = length
x
width
x
height
4 in. x 2 in. x 1 in. = 8 cubic inches (8 in.3)
This rectangular prism will hold 8 of the 1 inch cubes.