Circle (Diameter v. Radius)

1. What is the name of the blue line in the circle below?

Circle with diameter

2. What is the name of the blue line in the circle below?

Circle with radius

3. What is the length of a radius in the circle below?

Circle with 2m radius

4. What is the length of a radius in the circle below?

Circle with 4mm radius

5. What is the length of a radius in the circle below?

Circle with diameter 10 in

6. What is the length of a diameter in the circle below?

Circle with 20 in radius

7. What is the length of a diameter in the circle below?

Circle with diameter 3 ft


8. What is the length of a diameter in the circle below?

Circle with radius 4mm


9. If a circle has a diameter of 30 in, what is the length of its radius?


10. If a circle has a radius of 4 cm, what is the length of its diameter?


11. Draw a circle and draw 3 of its radii.


12. Draw a circle and draw 2 different diameters in it.

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