Question

Find the perimeter of a sector of a circle if it's measure is 180 degree and radius is 7cm​

Answer 1

GIVEN :-

• Central angle = 180°.
• Radius of sector of Circle = 7 cm.

TO FIND :-

• The Perimeter of a sector of circle.

SOLUTION :-

As we know that the perimeter of a sector of circle is given by,

➠ Perimeter = 2πr × 360°/∅ + 2r

• π = 22/7.
• r = radius of sector of a circle.
• ∅ = Central angle.

➠ Perimeter=2 × (22/7) × 7 × 360°/180° + 2 × 7

➠ Perimeter = 44/7 × 7 × 2 + 14

➠ Perimeter = 44 × 2 + 14

➠ Perimeter = 88 cm + 14

➠ Perimeter = 102 cm

Hence The Perimeter of a sector of circle is 102 cm.

ADDITIONAL INFORMATION :-

Area of sector of Circle :-

➠ Area = πr² × 360°/∅

• π = 22/7.
• r = radius of sector of a circle.
• ∅ = Central angle.

Answer 2

Given

• Angle (θ) = 180°
• Radius (r) = 7cm

To find

• Perimeter of the sector.

Solution

We know that

$\underline{\boxed{Perimeter\: of\: a\: sector = 2πr × \dfrac{360}{θ} + 2r}}$

$\begin{lgathered}\begin{lgathered}\begin{lgathered}\tt {\pink{Here}}\begin{cases} \sf{\green{π = \frac{22}{7}}}\\ \sf{\blue{r = 7cm}}\\ \sf{\orange{θ = 180°}}\end{cases}\end{lgathered} \:\end{lgathered}\end{lgathered}$

→ Perimeter of sector = 2 × 22/7 × 7 × 360/180 + 2(7)

→ Perimeter of sector = 44 × 2 + 14

→ Perimeter of sector = 88 + 14

→ Perimeter of sector = 102 cm

Hence, perimeter of the sector is 102 cm.

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