Find the radius of a circle in which a central angle of `72^(@)` intercept an arc of length of `22 cm`. (Use `pi =22/7`).

Explanation

Let the required radius be r cm. Then,
`l = 22 cm` and `theta = (72 xx pi/180)^(c )= ((2pi)/5)^(c )`.
Now, `theta = l/r rArr r = l/theta= (22 xx 5/(2pi)) cm`
`= (22 xx 5/2 xx 7/22) cm`
`= 35/2 cm = 17.5 cm`.
Hence, the radius of the circle is `17.5` cm.
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