You should be familiar with the concept of **scale factor** and calculating lengths of **similar** shapes.

Here, we will loot at questions involving **volume scale factor **.

__Example__

These two cubes are similar.

**Smaller cube length = 4 cm **

**Volume of the smaller cube = 64 cm³ **

**Larger cube length = 8 cm**

What is the volume of the larger cube?

__Method__

1. Find the **scale factor of length** by dividing corresponding lengths. 8 ÷ 4 = 2

2. **Cube the scale factor** 2 x 2 x 2 = 8

3. **Multiply** by the volume if you are finding the larger shape, **or divide** if you want the smaller shape. (In this case, we want the larger shape, so we multiply) 64 x 8 = 512 cm³

The step that students tend to forget is Step 2. You ** must** be able to recall that a scale factor of length needs to be

**in order to make a comparison of two shapes' volumes.**

__cubed__

__Example 2__

**Large cuboid length = 18 cm **

**Volume of large cuboid = 1620 cm³ **

**Small cuboid length = 6 cm**

What is the volume of the small cuboid?

__Method__

1. Find the **scale factor of length** by dividing corresponding lengths. 18 ÷ 6 = 3

2. **Cube the scale factor** 3 x 3 x 3 = 27

3. **Multiply** by the volume if you are finding the larger shape, **or divide** if you want the smaller shape. (In this case, we want the smaller shape, so we divide) 1620 ÷ 27 = 60 cm³