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If the surface area of a sphere is $1386 cm^{2}$ (take π = 22/7), its radius is:

Class 9Surface Area of a SphereMensuration

A10.5 cm
B21 cm
C7 cm
D14 cm

Step-by-Step Solution

4*π*

r^{2} = 1386

gives

r^{2} = 1386 \times 7/ (4 \times 22) = 9702/88 = 110.25

, so

r = 10.5

cm.

Answer: A) 10.5 cm

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