In a circle, if an are of length 220 cm subtends an angle of measure `63^(@)` at the centre ,then determine the radius of the circle.

Explanation

`63^(@)` is made by the are 220 cm
`therefore 1^(@)" is made is by are" (220)/(63)` cm
`therefore 360^(@)"is made by the are" (220xx360)/(63) cm =(8800)/(7) cm`
`therefore "the perimeter of the circle" =(8800)/(7)cm`
Let r be the radius of the circule.
`therefore 2pi=(8800)/(7) or, 2xx(22)/(7)xxr=(8800)/(7)` or, r=200.
Hence the radius of the circle =200 cm.