The figure shows one big quadrant and two small semicircles. The radius of the big quadrant is 78 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 78
= 244.92 m
Diameter of the big quadrant
= 78 x 2
= 156 m
Circumference of the big quadrant
= 3.14 x 156 x
14= 122.46 m
Perimeter of the shaded figure
= 244.92 + 122.46
= 367.38 m
(b)
Area of the big quadrant
= 3.14 x 78 x 78 x
14 = 4775.94 m
2 Area of the triangle
=
12 x 78 x 78
= 3042 m
2 Area of shaded area
= 4775.94 - 3042
= 1733.94 m
2 Answer(s): (a) 367.38 m; (b) 1733.94 m
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