Question

Find the area of annulus, whose inner
and outer radii are 15 cm and 18 cm
respectively.​

Answer 1

Step-by-step explanation:

$area \: of \: annulus = area \: o f \: outer - area \: of \: inner$

$= \pi ({r1})^{2} - \pi( {r2}^{2} )$

$\pi( \: {18}^{2} - {15}^{2} )$

=22/7(324-289)

=22/7×35

=22×5

=110cm^2

so..Area of annulus is 110 cm sq.!!!

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