annulus problem 1:
An annulus has a larger circle radius R of 14 cm and a smaller circle radius r of 8 cm.
a) calculate the area of the circle sector
b) calculate the the perimeter/circumference of the circle sector
perimeter/area:
diameter large (D): 2 * 14 = 28 cm
diameter small: (d): 2 * 8 = 16 cm
answer perimeter
perimeter = π * (D + d)
perimeter = π * (28 + 16)
perimeter = 138.23 cm
A: The perimeter of the circle is 138.23 centimeter.
answer area
area = π * (R² – r²)
area = π * (14² – 8²)
area = 414.69 cm²
A: The area of the circle sector is 414.69 square centimeters.