WALT: calculate the volume of cubes and

cuboids

- Count the squares- Use the formula:

- V = L x h x w

The ‘volume’ is the amount of space taken up by a 3D shape.

Formula:Volume = length x width x height

lengthwidth

height

Look at the cuboid and identify the 3 measurements that we will use to calculate volume: height, width and length.

length

width

height

Just as with area in the lessons last week, if the 3D shape is on a grid or made up of cubes, you can just count them to find the volume!

1 cube = 1 unit3

Volume is measured in cubed units or units cubed!

What is the volume of this shape?

Count the cubes!

1cm

15 cm3

Answer:

What is the volume of this shape?

1cm

Answer:

12cm3

What is the volume of this shape?

1cm

Answer:

10cm3

14cm3

What is the volume of this shape?

1cm

Look at this cube carefully

16cm3

1st layer

The other 3 layers all have the same volume as they aremade up of the same number of cubes.

Therefore…

16 x 4 = 64cm3

4cm

4cm

4cm

Volume = l × w × h= 4cm × 4cm × 4cm= 16cm × 4cm= 64cm3

Calculate the volume of this cuboid.

Volume = l × w × h= 3cm × 3cm × 4cm= 9cm × 4cm= 36cm3

4 cm

3cm

3cm

Calculate the volume of the cuboid below

5cm

4cm

3cm

Have a go!

5cm

4cm

3cm

Answer:

Volume = l × w × h= 5cm × 4cm × 3cm= 20cm × 3cm= 60cm3

Calculate the volume of the cube below:

10m3

Answer:As this shape is a cube, we know that all of the sides are equal length.

10m3

Volume = l × w × h= 10cm × 10cm × 10cm= 100cm × 10cm= 1000cm3

8cm

Find the missing length. The volume of the cuboid is 48cm3.

?cm

3cm

8cm

?cm

3cm

Volume = l × w × h

Therefore:

48cm3 = l x w x h

48cm3 = 8cm x 3cm x h

48cm ÷ 8cm = 6cm

6cm ÷ 3cm = 2cm

So the missing length is 2cm3

48cm3

Calculate the volume of the compound shape below:

Remember the strategy you used for area of compound shapes and do the same thing!

Divide the shape into two regular shapes…

Answer:

Part APart B

Part A

Volume = l × w × h

Volume = 5cm x 15cm x 10cm

Volume = 75cm x 10cm

Volume = 750cm3

Part B

Volume = l × w × h

Volume = 5cm x 5cm x 5cm

Volume = 25cm x 5cm

Volume = 125cm3

Total volume of shape: 750cm3 + 125cm3 = 875cm3

Now try the worksheets!