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प्रश्न
A solid metal sphere is cut through its center into 2 equal parts. If the diameter of the sphere is `3 1/2 cm`, find the total surface area of each part correct to two decimal places.
उत्तर
Diameter of sphere = `3 1/2 cm = 7/2 cm`
Therefore, radius of sphere = `7/4 cm`
Total curved surface area of each hemispheres = 2πr2 + πr2
= 3πr2
= `3 xx 22/7 xx 7/4 xx 7/4`
= `462/16 cm^2`
= 28.88 cm2
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