Find the radius of the circle with area S = 200 cm².

Result

r =  7.979 cm

#### Solution:

$S = 200 \ cm^2 \ \\ S = \pi r^2 \ \\ \ \\ r = \sqrt{ S/\pi } = \sqrt{ 200/3.1416 } \doteq 7.9788 = 7.979 \ \text { cm }$

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