# CD disc

A compact disc has a diameter of 11.8 cm. What is the surface area of the disc in square centimeters?

Result

S =  109.36 cm2

#### Solution:

$D = 11.8 \ cm \ \\ r = D/2 = 5.9 \ cm \ \\ \ \\ S = \pi r^2 = 109.36 \ cm^2$

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