[550 cm^2] Savitri had to make a model of a cylindrical kaleidoscope for her science project.She wanted to

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Savitri had to 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 would 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?

348 $cm^2$

468 $cm^2$

352 $cm^2$

550 $cm^2$

Explanation:

Radius of the base of the cylindrical kaleidoscope (r) = 3.5 cm.

Height (length) of kaleidoscope (h) = 25 cm.

Area of chart paper required = curved surface area of the kaleidoscope

= 2πrh = $2 \times \dfrac{22}{7} \times 3.5 \times 25$

= 550 $cm^2$

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Savitri had to 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 would 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?	Answer

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