If the radius of a circle is 4 cm and the sector angle is 30°, then the area of the sector is (A) 3π/4 sq.cm

Question

If the radius of a circle is 4 cm and the sector angle is 30°, then the area of the sector is

(A) \(\frac{3\pi}{4}\) sq.cm

(B) 3π

(C) 4π sq.cm

(D) \(\frac{4\pi}{3}\) sq.cm

Answer 1

Correct option is: (D)  \( \frac {4\pi}{3} \, sq. cm \)

\(\because\) Area of sector of angle 360° = Area of circle = \(\pi r^2\).

\(\therefore\) Area of sector of angle 30° = \(\frac {\pi r^2}{360°} \times 30° = \frac {\pi r^2}{12}\)

= \(\frac {\pi \times 4^2}{12} = \frac {4\pi}{3} \, cm^2\)

Answer 2

Correct option is: (D) \(\frac{4\pi}{3}\) sq.cm