Foundation November 2020 Paper 2 Q13
13.
(a) 
This solid prism is made from identical cubes. Each cube has sides of length 1 cm.
Give the dimensions of a cuboid that could be made with the same number of cubes. [1]
(b) 
The total surface area of a different cube is 144 cm\(^2\).
To work out the side length of this cube, Mai does the following calculations:
| \(\sqrt{144} = 12\) \(12 \div 6 = 2\) |
Mai’s method is incorrect.
Explain the mistake that Mai has made. [1]
| Scheme | Marks | Comments |
|---|---|---|
| 2 × 2 × 5 or 1 × 4 × 5 or 1 × 2 × 10 or 1 × 1 × 20 oe | B1 | Accept any clear representation of correct dimensions |
| Scheme | Marks | Comments |
|---|---|---|
| Correct explanation Eg ‘she needs to ÷ 6 first’ ‘ she has done things in the wrong order’ ‘you need to square root the area of a face’ ‘144 ÷ 6 first’ | B1 | Do not allow e.g ‘÷ 6’ ‘144 ÷ 6’ |
| (2) |