## Total Wall Thickness (2)

 Difficulty: Rating: GCSE Marks:

GCSE Text:
The wall of a new building contains different sections. The outer layer is made of red brick, and the inner layer is plaster. The design is shown in this diagram:

Calculate the total thickness of the wall in mm.

Suggestions:
This video was made when a school building was being constructed on site. KIER Construction kindly allowed a number of videos to be made so that students could grasp the use of Maths in the construction industry. In solving this problem, students need to handle many different units, therefore a class needs about 5 minutes of time to reach the final answer. You may need to provide the conversion rate of inches to cm/mm, or point them to a ruler to discover the conversion calculation themselves.

Extension Ideas:
Teachers could extend the learning by considering:

• Where are inches still used, despite the UK using a metric system of measurement?
• Convert the diagonal size of a 55″ tv screen to cm.
• Convert the diameter of a 29″ bike wheel to cm