Question

Calculate the area of the shaded region in the figure given in $c{m}^2.$

• A. 469.3
• B. 281.2
• C. 1120.4
• D. 2499.7

Answer 1

The correct option is A

469.3

Area of outer sector
$=\frac{140°}{360°}\times \pi \times 20cm\times 20cm$

Area of inner sector
$=\frac{140°}{360°}\times \pi \times 4cm\times 4cm$

Area of shaded region = Outer sector - Inner sector

$=\frac{140°\pi }{360°}(400c{m}^2-16c{m}^2)$

$=\frac{7}{18}\times \frac{22}{7}\times 384c{m}^2=469.3c{m}^2$