Geometrymedium · Past Paper
If the diameter of a circle increases by 100%, its area increases by:
A100%
B200%
C300%
D400%
✓ Correct Answer: C — 300%
Radius doubles (2r). New area = pi * (2r)^2 = 4 * pi * r^2. Increase = 3 * initial area = 300%.
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