Diameter to area

Find the area of a circle whose diameter is 26cm.

Result

A =  530.929 cm2

Solution:

$D = 26 \ \\ r = D/2 = 26/2 = 13 \ \\ A = \pi \cdot \ r^2 = 3.1416 \cdot \ 13^2 \doteq 530.9292 = 530.929 \ cm^2$

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