Geometry and TrigonometryEasyRadius from a diameter
Geometry and Trigonometry practice question
A round coaster has a diameter of 10 centimetres. What is its radius, in centimetres?
Answer: 5
The radius is half the diameter: 10 ÷ 2 = 5.
Common wrong answers
- If you answered 20
- 20 doubles the diameter.
- If you answered 100
- 100 is 10².
- If you answered 31.4
- 31.4 is the circumference.
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