In the figure below, GHJK and HJCB are squares. F and D are centres of square BCJH and GHJK respectively. E is the centre of HJ. If GB = 98 m, take π as
227 and find
- the perimeter of the shaded region,
- the area of the shaded region.
(a)
Circumference of big circle
=
227 x 49
= 154 m
Circuference of four small semicircles
= 4 x
12 x
227 x 24.5
= 154 m
Circumference of two quadrants
=
14 x 2 x
227 x 49
= 77 m
Perimeter of the shaded region
= 154 + 154 + 77
= 385 m
(b)
Area of big circle
=
227 x 24.5 x 24.5
= 1886.5 m
2Area of two shaded quadrant
=
12 x
227 x 24.5 x 24.5
= 943.25 m
2 Area of shaded region
= 1886.5 + 943.25
= 2829.75 m
2 Answer(s): (a) 385 m; (b) 2829.75 m
2 
