Foundation November 2017 Paper 3 Q13
13 A cube has edge length 0.9 metres.
Work out the total surface area of the cube.
Give your answer in square centimetres. [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| \(0.9^2\) or 0.81 | M1 | oe |
| 4.86 | A1 | |
| 48 600 | B1ft | ft their 4.86 \(\times\) 10 000 correctly evaluated their 4.86 cannot be 0.9 |
| Alternative method 2 | ||
| 90 (cm) | B1 | |
| (their 90)\(^2\) or 8100 | M1 | oe |
| 48 600 | A1ft | ft (their 90)\(^2 \times 6\) correctly evaluated |
Additional guidance
| In Alt 1, award the B1ft if their answer clearly comes from multiplying a value by 10 000, but not from \(0.9 \times 10\,000 = 9000\) | |
| 0.9 m = 9 cm \(9 \times 9 = 81\) (9 is their 90) \(81 \times 6 = 486\) | B0 M1 A1ft |
| No conversion shown \(9 \times 9 = 81\) (9 is their 90) \(81 \times 6 = 486\) | B0 M1 A1ft |
| \(0.9 \times 0.9 = 0.81\) and \(0.81 \times 0.9 = 0.729\) | M0 |
| \(0.9 \times 0.9 = 0.81\) and \(0.81 \times 0.9 = 0.729\) (\(0.729 \times 10\,000\)) = 7290 | M0A0 B1ft |