Answer:
1256.64
Step-by-step explanation:
To find the area of a circle, the formula is πr2.
R stands for radius, and since the radius of a circle is always half the diameter we can figure this problem out.
If the diameter is 40, the radius is 1/2 of that, so the radius is 20. Now knowing the radius is 20, plug that into our formula and then we'll get the answer.
A = πr2 = π · 20^2 ≈ 1256.63706
≈ 1256.64
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