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Question
A solid sphere metal is cut through its centre into 2 equal parts. If the diameter of the sphere is 3`1/3` cm , find the total surface of each part, correct to two decimal places.
Solution
Diameter of the sphere = 3`1/3` cm = `10/3` cm
Therefore, radius = `5/3` cm
Total curved surface area of each hemisphere = `3pir^2`
= `3 xx 22/7 xx 5/3 xx 5/3`
= 26.19 cm2
Total curved surface area of each hemisphere = 26.19 cm2
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