Answer :

Area of the sea over which the ships are warned

= Area of the sector

(having \(r \ = \ 16.5 \) km and \(\theta \ = \ 80° \))

\( = \ \frac{ \theta }{360} \ × \ \pi r^2 \)

\( = \ \frac{80}{360}\ × \ 3.14 \ × \ (16.5)^2 \)

\( = \ \frac{68389.2}{360} \)

\(= \ 189.97 \) km^{2}

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- Tick the correct answer in the following : Area of a sector of angle p (in degrees) of a circle with radius R is : (a) \( \frac{p}{180} \ × \ 2\pi R \) (b) \( \frac{p}{180} \ × \ \pi R^2 \) (c) \( \frac{p}{360} \ × \ 2\pi R \) (d) \( \frac{p}{720} \ × \ 2\pi R^2 \)

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