Calculate the area of a semicircle with a diameter of 25 cm.?
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- anonymousLv 77 years agoFavorite Answer
Calculate the area of a circle with diameter 25 cm , and the semicircle will have area one-half of that.
However, to do the area of a circle with diameter 25 cm, you need to use the radius of the circle, not the diameter. The radius is (1/2) the diameter, or 12.5 cm .
The area of the entire circle is
A = πr²
= π * (12.5 cm)²
= π * 156.25 cm²
The area of the semicircle is half of that, or
[ (π * 156.25 cm²) / 2 ]
= π * 78.125 cm²
That's the exact answer. Using a calculator to approximate the area of the semicirce, it is
A(semicircle) ≃ 245.44 cm²