Exact area = 25pi
Approximate area = 78.5
You can pick one or the other to have as your answer
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Explanation:
The formula you use is
A = pi*r^2
The radius is r = d/2 = 10/2 = 5
So,
A = pi*r^2 = pi*5^2 = pi*25 = 25pi
is the exact area
Replace pi with 3.14 to get 25*pi = 25*3.14 = 78.5
which is the approximate area
To get a better approximation, you would use more decimal digits of pi.
