Question

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# MathsAryabhatta
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A hollow cylinder is made up of copper. The volume of metal used in this pipe is 2640 cubic cm. If the external radius is 7 cm and height is 21 cm. Find thickness.
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Answer 1

༒࿐៚ Answer ༒࿐៚

Let R be the external radius of a pipe and r be the internal radius of a pipe.

R=7cm

h=21cm

Volume of hollow cylinder =

$( {r}^{2} - {r}^{2} )$

$2640 = \frac{22}{7} \times 21(49 - {r}^{2} ) \\ \\ 2640 = 66(49 - {r}^{2} )$