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प्रश्न
Find the area and perimeter of the circles with following: Diameter = 77cm
उत्तर
The radius of a Circle with diameter d is r = `"d"/(2)`
The Area of a Circle with radius r = πr2
The radius of a Circle with diameter 77 is r
= `(77)/(2)`
= 38.5cm
The Area of a Circle with radius r
= π(38.5)2
= `(22)/(7) xx (38.5)^2`
= 4658.5cm2
The Circumference of a Circle with diameter d is πd
The Circumference of a Circle with diameter 77 is π x 77
= `(22)/(7) xx 77`
= 242cm.
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