Higher November 2024 Paper 3 Q11
11 \(OAB\) is a sector of a circle with centre \(O\) and radius 4.7 m.
The sector has a perimeter of 34.3 m.
Find the size of the reflex angle \(AOB\).
Give your answer correct to the nearest degree. (3)
| Answer | Mark | Mark scheme |
|---|---|---|
| 304 | P1 | for start of process to find the arc length eg \(34.3 - 2 \times 4.7\ (= 24.9)\) or for forming a suitable equation eg \(\dfrac{\angle AOB}{360} \times \pi \times 2 \times 4.7 + 2 \times 4.7 = 34.3\) |
| P1 | for process to isolate the arc length in an equation eg \(\dfrac{\angle AOB}{360} \times \pi \times 2 \times 4.7 = \text{``}24.9\text{''}\) or for complete process to find \(AOB\) eg \(\angle AOB = \dfrac{\text{``}24.9\text{''} \times 360}{\pi \times 2 \times 4.7}\) | |
| A1 | answer in the range 303 to 304 |
Additional guidance
Condone omission of the addition of 2 radii in the equation for this mark only
eg \(\dfrac{\angle AOB}{360} \times \pi \times 2 \times 4.7 = 34.3\)
If an answer is given in the range in working and then rounded incorrectly award full marks