We can calculate the volume of 3D shapes to find their capacity or the amount of space they occupy. We can also find the surface area which indicates the total area of each of their faces.

The volume of a cuboid = width × length × height

Remember that volume is measured in units cubed: mm^{3}, cm^{3}, m^{3} etc.

To calculate the surface area of a cuboid you calculate the area of each face and add them together.

Remember that area is measured in units squared: mm^{2}, cm^{2}, m^{2} etc.

- Question
Calculate the volume and surface area of this wooden box which measures 20 cm by 35 cm by 15 cm.

\[\text{Volume = width} \times \text{length} \times \text{height}\]

**1.**Calculate the volume of the wooden box:Volume = 20 × 35 × 15 = 10,500 cm

^{3}**2.**Calculate the surface area by working out the area of each face and adding them together:The area of the base = 35 × 20 = 700 cm

^{2}The area of the top is the same = 700 cm

^{2}The area of the front = 35 × 15 = 525 cm

^{2}The area of the back is the same = 525 cm

^{2}The area of the left = 15 × 20 = 300 cm

^{2}The area of the right is the same = 300 cm

^{2}Total surface area = (2 × 700) + (2 × 525) + (2 × 300) = 3,050 cm

^{2}