Question P6 Circles and curved boundaries
A circle has radius 21 cm. Find its area. Use π = .
Answer
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Find the space inside a circle shape or the distance around its boundary.
In this one. Area measures the surface inside a shape. Use square centimetres, and take the appropriate fraction of the whole circle area.
'Area' asks for square centimetres from the radius. 'Circumference' or 'perimeter' on a curved edge asks for plain centimetres from the diameter instead.
Children give a circumference answer in square units, or find a circle's area without squaring the radius first, mixing up the two kinds of measurement.
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