The figure is made up of identical quadrants. The radius is 36 cm long. Take π as 3.14.
- Find the area of the shaded part.
- Find the perimeter of the shaded part.
(a)
Area of one circle
= 3.14 x 36 x 36
= 4069.44 cm
2 Area of
12 shaded leaf
= (4069.44 ÷ 4) - (
12 x 36 x 36)
= 369.36 cm
2 Area of four
12 shaded leaf
= 369.36 x 4
= 1477.44 cm
2 Area of the shaded part
= 4069.44 + 1477.44
= 5546.88 cm
2 (b)
Length of combined curved lines
= 3.14 x 36 x 2 x 2
= 452.16 cm
Length of 12 straight lines
= 36 x 12
= 432 cm
Perimeter of the shaded part
= 452.16 + 432
= 884.16 cm
Answer(s): (a) 5546.88 cm
2; (b) 884.16 cm