If the surface area of a sphere is 346.5 cm2, then its radius

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If the surface area of a sphere is 346.5 cm2, then its radius (taking π = 22/7) is

1. 7 cm
2. 3.25 cm
3. 5.25 cm
4. 9 cm

Correct Option: C

Surface area of sphere = 4πr²

∴ 4 ×	22	× r² = 346.5
	7

⇒ 4 × 22 × r² = 346.5 × 7

⇒ r² =	346.5 × 7	= 27.5625
	4 × 22

∴ r = √27.5625 = 5.25 cm