Question

Find the perimeter and area of a semi circle of radius 10.5 cm

Answer 1

Answer:

perimeter=32.97=πr

area=173=π*r*r/2

Answer 2

Answer :

Given:

• The radius of semi - circle = 10.5 cm.

Find :

• The perimeter of the semi - circle.
• The area of the semi - circle

Solution :

$\dag$Formula for Perimeter of semi - circle

$\boxed{\bold {\dfrac {2×pi×radius}{2}}}$

$\:$

The perimeter of the semi-circle :-

➟ ${\bold {\dfrac {2×pi×radius}{2}}}$

➟${\bold {\dfrac {2×\dfrac {22}{7}×10.5}{2}}}$

➟${\bold {\dfrac {2×22×1.5}{2}}}$

➟${\bold {\dfrac {66}{2}}}$

➟${\bold {33cm}}$

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$\dag$Formula for Area of semi - circle

$\boxed{\bold {\dfrac {pi×{radius}^{2}}{2}}}$

The area of the semi - circle :-

➟ ${\bold {\dfrac {pi×{radius}^{2}}{2}}}$

➟ ${\bold {\dfrac {\dfrac {22}{7}×{10.5}^{2}}{2}}}$

➟ ${\bold {\dfrac {\dfrac {22}{7}×110.25}{2}}}$

➟ ${\bold {\dfrac {22×15.75}{2}}}$

➟ ${\bold {\dfrac {346.5}{2}}}$

➟ ${\bold {173.25 \:cm\: square }}$

•°• the Perimeter of the semi circle is 33 cm and area is 173.25 cm square.

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