The figure shows a rectangular park which consists of 1 playground in a semi-circle shape and a pond. 4 quarter circles make up the shape of the pond. The length and breadth of the rectangle are 72 m and 22 m respectively.
- Find the perimeter of the pond.
- Find the area of the shaded part. (Take π = 3.14).
(a)
Perimeter of the pond = Circumference of 1 circle + 72
= 3.14 x 36 + 72
= 113.04 + 72
= 185.04 m
(b)
Area of the shaded region = Area of the rectangle - Barbeque area - Pond area
= 72 x 22 -
12 x 3.14 x 13 x 13 - (
12 x 3.14 x 18 x 18 + 36 x 18 + 2 ( (18 x 18) -
14 x 3.14 x 18 x 18))
= 1584 - 265.33 - (508.68 + 648 + 2 ( - 254.34))
= 1584 - 265.33 - 648
= 670.67 m
2 Answer(s): (a) 185.04 m; (b) 670.67 m
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