PSLE The outline of the shaded figure is formed by 3 identical small quarter circles, 2 identical large quarter circles and 3 straight lines. Take π = 3.14
- What is the radius of the large quarter circle?
- Find the perimeter of the shaded figure.
(a)
Length of AB
= Length of BC
= 22 ÷ 2
= 11 cm
Radius of the large quarter circle
= 22 + 11
= 33 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 33
= 51.81 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 22
= 34.54 cm
Perimeter of the shaded figure
= 2 x 51.81 + 3 x 34.54 + 2 x 11 + 22
= 103.62 + 103.62 + 44
= 251.24 cm
Answer(s): (a) 33 cm; (b) 251.24 cm