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Question
Find the diameter of the sphere for the following :
Surface Area = 221. 76 cm2
Solution
Surface Area = 221. 76 cm2
Surface area = `4pir^2`
⇒ `4pir^2 = 221.76`
⇒ `4 xx 22/7 xx r^2 = 221.76`
⇒ `r^2 = (221.76 xx 7)/(4 xx 22)`
⇒ `r^2 = 17.64`
⇒ r = 4.2 cm
Radius = 4.2 cm ⇒ Diameter = 2r = 8.4 cm
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