Mensurationmedium · Past Paper
If the curved surface area of a sphere is 154 cm², find its diameter.
A3.5 cm
B7 cm
C14 cm
D10.5 cm
✓ Correct Answer: B — 7 cm
4πr² = 154 => 4 * (22/7) * r² = 154 => r² = 154 * 7 / 88 = 12.25 => r = 3.5 cm. Diameter = 7 cm.
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