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Year 5 Maths — Circles: centre, radius and diameter

Name the centre, radius and diameter of a circle, and use the fact that the diameter is twice the radius.

Name: ________________________

  1. 1.Every measurement here is in centimetres. Sort each circle by whether its diameter is below 20 or above 20.

    Groups: Diameter below 20 · Diameter above 20

    • radius 15
    • radius 12
    • radius 6
    • radius 8
    • diameter 15
    • diameter 26

  2. 2.Tap the radius.

    Write the number of the part.

    123

  3. 3.A round table top has a diameter of 90 cm. How far is it from the middle of the table to its edge, in centimetres?

    • a) 90
    • b) 30
    • c) 45
    • d) 180

  4. 4.A circle has a diameter of 20 cm. What is its radius, in centimetres?

    • a) 5
    • b) 10
    • c) 40
    • d) 20

  5. 5.Put these circles in order by size, smallest first.

    • radius 7
    • radius 2
    • diameter 6
    • radius 4
    • diameter 10

  6. 6.What is the name for a straight line drawn from the middle of a circle out to its edge?

  7. 7.Tap the centre that is marked.

    Write the number of the part.

    123

  8. 8.A circle has a radius of 6 cm. What is its diameter, in centimetres?

    • a) 6
    • b) 36
    • c) 3
    • d) 12

Answer key — Year 5 Maths — Circles: centre, radius and diameter

  1. 1. radius 6 → Diameter below 20; radius 12 → Diameter above 20; diameter 15 → Diameter below 20; diameter 26 → Diameter above 20; radius 8 → Diameter below 20; radius 15 → Diameter above 20
  2. 2. 1 — The radius
  3. 3. c) 45
  4. 4. b) 10
  5. 5. 1. radius 2 2. diameter 6 3. radius 4 4. diameter 10 5. radius 7
  6. 6. radius
  7. 7. 3 — The centre
  8. 8. d) 12