exercise: circle sector problem 1
A circular sector has a radius of 18 cm and a central angle of 88°.
a) calculate the arc length
b) calculate the the perimeter/circumference of the circle sector
c) calculate the area of the circle sector
answer: circle sector problem 1
a) answer arc length
diameter (d) = 2 * 18 ⇒ 36 cm
arc length = d * π * α : 360
arc length = 36 * π * 88 : 360
arc length = 27.65 cm
A: The arc length is 27,65 centimeter.
b) answer perimeter
perimeter = 2 * radius + arc length
perimeter = 2 * 18 + 27,65
perimeter = 63.65 cm
A: The perimeter of the circle is 56.55 centimeter.
c) answer area
A = r² * π * α : 360
A = 18² * π * 88 : 360
A = 248.81 cm²
A: The area of the circle sector is 248.81 square centimeters.