Volume Vocabulary
Build the Layers
Find the Volume
Expressions & Equations
Volume Detectives
100

What is a unit cube

A cube that measures 1 unit × 1 unit × 1 unit and has a volume of 1 cubic unit.

100

A rectangular prism has a base that is 4 cubes long and 3 cubes wide.

How many cubes are needed to build ONE complete layer?

Answer: 12 cubes
4 × 3 = 12

100

Basic Dimensions

A rectangular prism is 4 units long, 2 units wide, and 3 units high.

What is the volume?

4 × 2 × 3 = 24 cubic units

100

A rectangular prism is 5 units long, 2 units wide, and 3 units high.

Which expression represents its volume?

A. 5 + 2 + 3
B. 5 × 2 × 3
C. 5 × 2 + 3
D. 5 + 2 × 3

B. 5 × 2 × 3

100

 Find the Mistake

A student finds the volume of a prism with dimensions 5 × 2 × 3 like this:

5 + 2 + 3 = 10 cubic units

What mistake did the student make?

The student added the dimensions instead of multiplying them.

Correct: 5 × 2 × 3 = 30 cubic units

200

Why do we measure volume in cubic units instead of square units?

Answer:
Because volume measures the space inside a 3-dimensional figure using unit cubes.

Examples: cm³, in³, ft³

200

A rectangular prism has 15 cubes in each complete layer.

If the prism has 3 equal layers, how many cubes fill the entire prism?

Answer: 45 cubic units
15 × 3 = 45

200

A rectangular prism has a base area of 15 square units and a height of 4 units.

What is the volume?

15 × 4 = 60 cubic units

200

 What Do the Factors Mean?

A prism has 8 cubes in each layer and 4 layers.

The expression 8 × 4 represents its volume.

What does each factor represent?

8 = cubes in each complete layer
4 = number of layers

200

Missing Height

A rectangular prism has a base area of 12 square units and a volume of 48 cubic units.

What is the missing height?

Answer: 4 units

12 × 4 = 48

300

In a rectangular prism, what does the base help us determine when finding volume?

The base helps us determine how many unit cubes are in one complete layer.

Area of Base = length × width

300

A rectangular prism has a volume of 48 cubic units. Each complete layer contains 12 cubes.

How many equal layers does the prism have?

Answer: 4 layers
48 ÷ 12 = 4

300

A rectangular prism has 12 unit cubes in each complete layer. There are 5 equal layers.

What is the volume?

12 × 5 = 60 cubic units

300

Match the Prism

Three prisms have these dimensions:

Prism A: 3 × 3 × 4
Prism B: 6 × 2 × 3
Prism C: 4 × 2 × 5

Which prism can be represented by the expression:

(6 × 2) × 3

 Prism B

Why?
6 × 2 represents the area of the base, and 3 represents the height/number of layers.

300

Who Is Correct?

A prism has 15 cubes in each layer and 4 layers.

  • Maya: 15 + 4 = 19 cubic units
  • Jordan: 15 × 4 = 60 cubic units

Who is correct, and why?

Answer: Jordan because volume can be found by multiplying the cubes in one complete layer by the number of equal layers.

15 × 4 = 60 cubic units

400

A rectangular prism has 6 equal layers of cubes.

What is the height, and what does the height tell us?

The height is 6 units. It tells us there are 6 equal layers stacked in the prism.

400

A rectangular prism is only partially filled with cubes. You can see that its base is 5 cubes long and 2 cubes wide, and the prism is 4 cubes high.

How can you determine the volume without filling in or counting every cube?

Answer:
Find one complete layer:

5 × 2 = 10 cubes per layer

Then multiply by the number of layers:

10 × 4 = 40 cubic units

⭐ Volume = 40 cubic units

400

A storage box is shaped like a rectangular prism. It measures:

8 inches long × 3 inches wide × 4 inches high

What is the volume of the box?

8 × 3 × 4 = 96 cubic inches

400

Which Expression Belongs?

A rectangular prism has a base that is 7 units long and 3 units wide. It is 4 units high.

Which TWO expressions can be used to find its volume?

A. 7 × 3 × 4
B. 21 × 4
C. 7 + 3 + 4
D. 10 × 4

 A and B

Because:

7 × 3 = 21 cubes in one layer

So:

7 × 3 × 4 = 21 × 4 = 84 cubic units

400

Missing Dimension Detective

A rectangular prism has a volume of 72 cubic units.

  • Length = 6 units
  • Width = 3 units
  • Height = ?

What is the missing height?

Answer: 4 units

6 × 3 = 18
72 ÷ 18 = 4

500

I am a 3-D solid figure with 6 rectangular faces. You can find the amount of space inside me by multiplying my length × width × height.

What am I, and what is the measurement of the space inside me called?

The figure is a right rectangular prism, and the amount of space inside it is called volume.

500

A rectangular prism will have a volume of 96 cubic units when completely filled.

One complete layer contains 16 unit cubes.

The prism currently has 2 complete layers built.

How many MORE complete layers are needed to finish the prism?

Answer:

96 ÷ 16 = 6 total layers

6 − 2 = 4 more layers

✅ 4 additional complete layers are needed.

500

A rectangular prism has a volume of 120 cubic units. Its base is 5 units long and 4 units wide.

What is the height of the prism?

Answer:
5 × 4 = 20 square units in the base
120 ÷ 20 = 6 units high

500

Expression Detective

Jada says the expression 12 × 5 represents the volume of a rectangular prism.

Marcus says:


“The 12 must be the length of the prism, and the 5 must be the width.”


Is Marcus correct? Explain what 12 and 5 could represent.

No.

12 could represent the number of cubes in one complete layer (area of the base), and 5 could represent the number of equal layers (height).

Therefore:

12 × 5 = 60 cubic units.

500

Challenge: Same Volume, Different Prism

Prism A has dimensions:

5 × 2 × 6

Prism B has:

  • Length = 3 units
  • Width = 4 units
  • Height = ?

Both prisms have the same volume.

What is the missing height of Prism B? Explain how you know.

Prism A:
5 × 2 × 6 = 60 cubic units

Prism B's base:
3 × 4 = 12 square units

60 ÷ 12 = 5 units

✅ Height = 5 units