Intermediate November 2021 Unit 1 Q13
13. Calculate the total perimeter of a semicircle of radius 4 cm.
Take \(\pi\) to be 3·14. [3]
| Scheme | Marks | Comments |
|---|---|---|
| (Curved length =) 3·14 × 4 or equivalent = 12·56 (cm) | M1 A1 | Do not allow M1 if subsequently divided by 2. Allow 4π 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 4π + 8. |