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
$=\frac{140}{360}\times \pi \times 20\times 20$

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

Area of shaded region = Outer sector - Inner sector

$=\frac{140\pi }{360}(400-16)$

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