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
= 26 ÷ 2
= 13 cm
Radius of the large quarter circle
= 26 + 13
= 39 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 39
= 61.23 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 26
= 40.82 cm
Perimeter of the shaded figure
= 2 x 61.23 + 3 x 40.82 + 2 x 13 + 26
= 122.46 + 122.46 + 52
= 296.92 cm
Answer(s): (a) 39 cm; (b) 296.92 cm