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Savitri had t o make a model of a cylind...

Savitri had `t o` make a model of a cylindrical Kaleidoscope for her science project. She wanted to use chart paper to make the curved surface of the Kaleidoscope. What should be the area of chart paper required by her, if she wanted to make a Kaleidoscope of length 25 cm with a 3.5 cm radius?

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Here, radius(r)=3.5cm and height(h)=25cm
As we know that kaleidoscope is in cylindrical shape so apply the C.S.A of cylinder=`2xxpixxrxxh`
`2xx22/7xx3.5xx25`=`550 cm^2`
Hence, Required area is `550 cm^2`.
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