The figure shows one big quadrant and two small semicircles. The radius of the big quadrant is 70 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 70
= 219.8 m
Diameter of the big quadrant
= 70 x 2
= 140 m
Circumference of the big quadrant
= 3.14 x 140 x
14= 109.9 m
Perimeter of the shaded figure
= 219.8 + 109.9
= 329.7 m
(b)
Area of the big quadrant
= 3.14 x 70 x 70 x
14 = 3846.5 m
2 Area of the triangle
=
12 x 70 x 70
= 2450 m
2 Area of shaded area
= 3846.5 - 2450
= 1396.5 m
2 Answer(s): (a) 329.7 m; (b) 1396.5 m
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