Q5 of 64 Page 74

Find the area of a sector whose radius and perimeter are 20 cm and 110 cm respectively.

perimeter of a sector = 110 cm


radius = 20 cm


Perimeter = r + r + length of arc


= 2 ( r) + length of arc


110 =arc length + 2(20)


Arc length (a)= 110 – 40 = 70cm


Area of sector =



⇒ area of sector = 700 cm2


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