Question
Volume of material used in constructing a hollow
cylinder of height 24 cm and thickness 1 cm is 96Ï€. What is the sum of the internal and external radii?Solution
Let external and internal radius of the cylinder be R and r cm respectively. Thickness of cylinder (R - r) = 1 cm. Height of the radius h = 24 cm As we know, Volume of hollow cylinder = π (R2 – r²) h π (R2 – r²) h = 96π  π (R + r) (R - r) h = 96π  (R+ r) x 1 x 24 = 96  (R+ r) = 96/24  (R + r) = 4 cm
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