Question

Find area of the circle having radius 21cm.

Answer 1

Given :

• Radius of Circle = 21 cm

To Find :

• Area of Circle = ?

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SolutioN :

$\dag$ Formula Used :

• ${\underline{\boxed{\pmb{\sf{ Area {\small_{(Circle)}} = \pi {r}^{2} }}}}}$

Where :

• r = Radius

$\dag$ Calculating the Area :

${\longmapsto{\qquad{\sf{ Area = \pi {r}^{2} }}}} \\ \\ \\ \ {\longmapsto{\qquad{\sf{ Area = \dfrac{22}{7} \times {21}^{2} }}}} \\ \\ \\ \ {\longmapsto{\qquad{\sf{ Area = \dfrac{22}{7} \times 21 \times 21 }}}} \\ \\ \\ \ {\longmapsto{\qquad{\sf{ Area = \dfrac{22}{\cancel7} \times \cancel{21} \times 21 }}}} \\ \\ \\ \ {\longmapsto{\qquad{\sf{ Area = 22 \times 3 \times 21 }}}} \\ \\ \\ \ {\longmapsto{\qquad{\sf{ Area = 66 \times 21 }}}} \\ \\ \\ \ {\qquad \; \; {\longmapsto \; {\pmb{\underline{\boxed{\purple{\frak{ Area = 1386 \; {cm}^{2} }}}}}}}}$

$\therefore \;$ Area of the Circle is 1386 cm² .

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