Question

Three sector of a circle 7cm making angle 60 ,80, 40 at centre are shaded find the area of the shaded region.

Answer 1

Answer:

Step-by-step explanation:

Area of the shaded region= area of the circle-area of the non- shaded region=πr^2-180/360*πr^2

=π×7*7-(7*7×π)/2

=π(49-49/2)

=π(49-24.5)

=22/7*24.5

=77cm^2

Answer 2

Answer:

Step-by-step explanation:

Area of a circular sector is $A=\pi\times r^2\times\frac{C}{360}$

where,

C  is the central angle in degrees

r  is the radius of the circle of which the sector is part.

Given,

r=7 cm

$C_1=60, C_2=80\text{ and }C_3=40$

Therefore the required area

$A=\pi\times r^2\times\frac{C_1}{360}+\pi\times r^2\times\frac{C_2}{360}+\pi\times r^2\times\frac{C_3}{360}\\\\\Rightarrow A=\pi\times r^2\times\frac{1}{360}(C_1+C_2+C_3)\\\\\Rightarrow A=\frac{22}{7}\times 7^2\times\frac{1}{360}(60+80+40)\\\\\Rightarrow A=\frac{22}{7}\times 7^2\times\frac{1}{360}\times180\\\\\Rightarrow A=77$

Therefore the area of the shaded region=$77\text{ cm}^{2}$