Higher November 2021 Unit 1 Q4
4. Calculate the total perimeter of a semicircle of radius 4 cm.
Take \(\pi\) to be 3·14. [3]
| Scheme | Marks | Comments |
|---|---|---|
| (Curved length =) \(3{\cdot}14 \times 4\) or equivalent | M1 | Do not allow M1 if subsequently divided by 2. |
| \(= 12{\cdot}56\) (cm) | A1 | Allow \(4\pi\) for M1A1. Allow SC1 for an answer of 25·12 (whole circle). (If 12·56 shown, but then doubled, only award the SC1.) |
| (Perimeter =) 20·56 (cm) | B1 | FT ‘their derived 12·56’ + 8 (even ‘an area’ + 8). Allow \(4\pi + 8\). |