# 10.03 Volume of rectangular prisms

Lesson

## Ideas

Let's review how to find the area of a rectangle to help us in this lesson.

### Examples

#### Example 1

Find the area of the rectangle shown.

Worked Solution
Create a strategy

Use the area of a rectangle formula: \text{Area}=\text{Length} \times \text{Width}

Apply the idea

We can see that length is 12 \text{ cm} and the width is 2 \text{ cm}.

Idea summary

When we calculate area, the unit of measurement is squared. If we have sides measured in centimetres \text{(cm)}, for example, the area will be \text{cm}^2.

## Volume with unit cubes

Let's look at how we can use unit cubes to find the volume of an object.

### Examples

#### Example 2

In this figure, 1\text{ block}=1\text{ cm}^3. What is the volume of the solid figure?

Worked Solution
Create a strategy

Count the total number of blocks.

Apply the idea

There are 10 blocks in the solid.

\text{Volume}=10\text{ cm}^3

Idea summary

Volume means the amount of space a 3D shape takes up.

## Volume of rectangular prisms

Let's see how to calculate the volume of rectangular prisms in this video.

### Examples

#### Example 3

Find the volume of the rectangular prism shown.

Worked Solution
Create a strategy

We can find the volume of a rectangular prism using the formula:

\text{Volume of a rectangular prism}=\text{Length}\times\text{Width}\times\text{Height}

Apply the idea
Idea summary

When we find the volume of a rectangular prism, we need to multiply together three measurements:

• length (l)

• width (w)