Question

8. The length of a chain used as the boundary of a semicircular park is
90 m. Find the area of the park.
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Answer 1

Length of the boundary of the semicircular park = 90 m

→πr + 2r =90

→r(22/7 + 2) = 90

→r = (90×7)/36

→r = 17.5 m

Area of the semicircular park = 1/2πr²

= 1/2×22/7×17.5×17.5

= 481.25 sq m