Circles, SM-Bank 052

Calculate the total perimeter of the sector below, giving your answer correct to the nearest whole number. (2 marks)

NOTE: \(\text{Perimeter}=2\times \text{radius}+\text{arc length}\)

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\(1128\ \text{km (nearest whole number)}\)

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\(\text{Perimeter}=2\times \text{radius}+\text{arc length}\)

\(\text{Perimeter}\)	\(=2r+\dfrac{\theta}{360}\times 2\pi r\)
	\(=2\times 300+\Bigg(\dfrac{120}{360}\times 2\pi \times 300\Bigg)\)
	\(=1128.3185\dots\)
	\(=1128\ \text{km (nearest whole number)}\)