Mensurationmedium · Past Paper
Two spheres have surface areas in the ratio 16:25. What is the ratio of their radii?
A4:5
B16:25
C2:5
D256:625
✓ Correct Answer: A — 4:5
A1/A2 = (r1/r2)² => 16/25 = (r1/r2)² => r1/r2 = sqrt(16/25) = 4/5.
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