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
= 17 ÷ 2
= 8.5 cm
Radius of the large quarter circle
= 17 + 8.5
= 25.5 cm
(b)
Circumference of each large quarter
=
14 x 2 x 3.14 x 25.5
= 40.035 cm
Circumference of each small quarter circle
=
14 x 2 x 3.14 x 17
= 26.69 cm
Perimeter of the shaded figure
= 2 x 40.035 + 3 x 26.69 + 2 x 8.5 + 17
= 80.07 + 80.07 + 34
= 194.14 cm
Answer(s): (a) 25.5 cm; (b) 194.14 cm