Question
A sphere is melted to form 81 identical cylinders. If
radius of each cylindrical is 1/3rd of the radius of sphere and height of each cylinder is 4 cm, then find the radius of sphere.Solution
Let radius and height of each cylinder be โrโ cm. So, radius of sphere = 4r cm Volume of sphere = 81ย ร volume of each cylinder => (4/3)ฯ(3r)3ย = 81 ร ฯ ร r2ย ร 4ย ย => 9r = 81 => r = 9 So, required radius = 3r = 27 cm
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