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
= 27 ÷ 2
= 13.5 cm
Radius of the large quarter circle
= 27 + 13.5
= 40.5 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 40.5
= 63.585 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 27
= 42.39 cm
Perimeter of the shaded figure
= 2 x 63.585 + 3 x 42.39 + 2 x 13.5 + 27
= 127.17 + 127.17 + 54
= 308.34 cm
Answer(s): (a) 40.5 cm; (b) 308.34 cm