The figure shows one big quadrant and two small semicircles. The radius of the big quadrant is 80 m.
- Find the perimeter of the shaded figure. (Take π = 3.14)
- Find the shaded area of this figure. (Take π = 3.14)
(a)
Circumference of the small circle
= 3.14 x 80
= 251.2 m
Diameter of the big quadrant
= 80 x 2
= 160 m
Circumference of the big quadrant
= 3.14 x 160 x
14= 125.6 m
Perimeter of the shaded figure
= 251.2 + 125.6
= 376.8 m
(b)
Area of the big quadrant
= 3.14 x 80 x 80 x
14 = 5024 m
2 Area of the triangle
=
12 x 80 x 80
= 3200 m
2 Area of shaded area
= 5024 - 3200
= 1824 m
2 Answer(s): (a) 376.8 m; (b) 1824 m
2