Worksheets · Foundation and Higher

Arc lengths and sectors

3 exam-style questions. Answers and the mark for each step are on the last page.

  1. Question 1Calculator · 3 marks

    A round pizza has a diameter of 30 cm. It is cut into 8 equal slices from the centre.

    (a) Work out the area of one slice. Give your answer correct to 3 significant figures. (3)

  2. Question 2Non-calculator · 4 marks

    A sector has angle 45∘45^\circ and area 8π8\pi cm².

    (a) Find the radius of the sector. (2)

    (b) Find the exact arc length of the sector. (2)

  3. Question 3Non-calculator · 6 marks

    A sector OABOAB of a circle has radius 6 cm. The area of the sector is 15π cm215\pi\text{ cm}^2.

    (a) Work out the angle AOBAOB. (2)

    (b) Work out the perimeter of the sector. Give your answer in the form a+bπa + b\pi. (2)

    (c) The sector is folded so that OAOA meets OBOB, making a cone with no base. Work out the radius of the base of the cone. (2)

Answers and marks

Question 1

(a) 88.4 cm288.4\text{ cm}^2

  • P1 The whole area with radius 15.
  • P1 Dividing by 8 (or multiplying by 45360\frac{45}{360}).
  • A1 88.4 cm288.4\text{ cm}^2 (awrt 88.4).

Question 2

(a) 88 cm

  • M1 Write the sector area as a fraction of πr².
  • A1 Correct answer: 88 cm

(b) 2π2\pi

  • M1 Take the same fraction of the circumference.
  • A1 Correct answer: 2π2\pi

Question 3

(a) 150∘150^\circ

  • P1 Setting up θ360×36π=15π\frac{\theta}{360} \times 36\pi = 15\pi.
  • A1 Correct answer: 150∘150^\circ.

(b) 12+5π12 + 5\pi cm

  • M1 Arc length 150360×12π\frac{150}{360} \times 12\pi.
  • A1 Correct answer: 12+5π12 + 5\pi.

(c) 2.5 cm

  • P1 Recognising that the arc length equals the base circumference.
  • A1 Correct answer: 2.5 cm.

Get your working marked

Arc lengths and sectors

Type your working online and see every mark you earned and lost.

Independent practice for Pearson Edexcel GCSE Mathematics (1MA1), not endorsed by Pearson.

Privacy · Terms