WAEC - Mathematics (2001 - No. 40)
A sector of a circle radius 14 cm subtends an angle 135° at the center of the circle. What is the perimeter of the sector? Take \(\pi = \frac{22}{7}\)
47cm
61cm
88cm
231cm
คำอธิบาย
Perimeter of the sector = \(2r + \frac{\theta}{360} \times 2\pi r\)
= \(2(14) + \frac{135}{360} \times 2 \times \frac{22}{7} \times 14\)
= \(28 + 33\)
= 61 cm