1. Surface Area and volume of
cuboids
LO: to be able to understand how to workout the area and
perimeter of a three dimensional shape
Starter- Name the shapes below
2. The volume of a cuboid is found by
multiplying its length by its width by
its height.
Volume of a cuboid= length x width x
height
Simple question
3cm
5cm
4cm
4. Level 6
10cm
Find the surface area and
4cm the volume
2lw + 2lh+ 2wh
8cm
Formula!
5. A cereal box has length 20 cm, height 30 cm
and width of 8 cm.
Find the surface area of the box.
6. The solution
To find the surface are of the box we need to find the area of each rectangular face
and add them all up.
The area of the front face is 20 x 30 = 600 cm2.
The area of the top face is 20 x 8 = 160 cm2.
The area of the side face is 8 x 30 = 240 cm2.
Now add these together to get 600 + 160 + 240 = 1000 cm2.
IMPORTANT: This is not our final answer! Cuboids have 6 faces in total. We have
only added three so far! For every front there is a back, for every top there is a
bottom, and for every side there is another other side.
This means we need to double our answer to get 1000 x 2 = 2000 cm2
