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
= 24 ÷ 2
= 12 cm
Radius of the large quarter circle
= 24 + 12
= 36 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 36
= 56.52 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 24
= 37.68 cm
Perimeter of the shaded figure
= 2 x 56.52 + 3 x 37.68 + 2 x 12 + 24
= 113.04 + 113.04 + 48
= 274.08 cm
Answer(s): (a) 36 cm; (b) 274.08 cm