Mensurationmedium · Past Paper
Ratio of areas of two circles is 4:9. Ratio of their circumferences is:
A2 : 3
B4 : 9
C16 : 81
Dsqrt(2) : sqrt(3)
✓ Correct Answer: A — 2 : 3
Area ratio = r1^2/r2^2 = 4/9 => r1/r2 = 2/3. Circumference ratio = r1/r2 = 2/3.
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