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
= 29 ÷ 2
= 14.5 cm
Radius of the large quarter circle
= 29 + 14.5
= 43.5 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 43.5
= 68.295 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 29
= 45.53 cm
Perimeter of the shaded figure
= 2 x 68.295 + 3 x 45.53 + 2 x 14.5 + 29
= 136.59 + 136.59 + 58
= 331.18 cm
Answer(s): (a) 43.5 cm; (b) 331.18 cm