Question

Find the area of the given sector, if it's radius is 3 ft. (Round off to 2 decimal places)
$\text{[Take 𝛑=}\frac{22}{7}]$

• A. 14.14 sq. ft
• B. 6.13 sq. ft
• C. 12.25 sq.ft
• D. 28.28 sq. ft

Answer 1

The correct option is B 6.13 sq. ft

We know,
Area of whole cirlce = $𝛑r^2$
= $\frac{22}{7}\times 3\times 3$
= 28.28 sq. ft

For 360° central angle, Area = $𝛑r^2$
For 1° central angle, Area = $𝛑r^2\times \frac{1}{360}$

For 78° central angle, Area = $𝛑r^2\times \frac{78}{360}$

= $28.28\times \frac{78}{360}$

= 6.127 sq. ft

= 6.13 sq. ft