The figure is made up of identical quadrants. The radius is 23 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 23 x 23
= 1661.06 cm
2 Area of
12 shaded leaf
= (1661.06 ÷ 4) - (
12 x 23 x 23)
= 150.765 cm
2 Area of four
12 shaded leaf
= 150.765 x 4
= 603.06 cm
2 Area of the shaded part
= 1661.06 + 603.06
= 2264.12 cm
2 (b)
Length of combined curved lines
= 3.14 x 23 x 2 x 2
= 288.88 cm
Length of 12 straight lines
= 23 x 12
= 276 cm
Perimeter of the shaded part
= 288.88 + 276
= 564.88 cm
Answer(s): (a) 2264.12 cm
2; (b) 564.88 cm