Shape and Space 7
2 marks · HardFind the length of the arc of a circle with radius 12 cm and angle 40° at the centre. Give your answer to 2 decimal places.
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Show answer
8.38 cm (±0.02)
Common mistakes: using incorrect fraction of angle; using diameter not radius
Show mark scheme and worked solution
Marking points
M1 · 1 mark · Uses correct arc length formula: (θ/360) × 2πr.
A1 · 1 mark · Arrives at 8.38 cm (2 dp).
Worked solution
Arc length = (θ/360) × 2πr