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Question
A cylinder has a diameter of 20 cm. The area of the curved surface is 100 cm2 (sq. cm). Find the height of the cylinder correct to one decimal place.
Solution
Diameter of the cylinder = 20 cm
Hence, Radius (r) = 10 cm
Height = h cm
Curved surface area = 2πrh
∴ 2πrh = 100 cm2
`=> 2 xx 22/7 xx 10 xx h = 100`
`=> h = (100 xx 7)/(22 xx 10 xx 2)`
= `35/22`
`=>` h = 1.6 cm
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