Exact Area = 98pi
Approximate Area = 307.8760800518 (use calculator stored version of pi)
Approximate Area = 307.72 (using pi = 3.14)
Units are in square millimeters
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Explanation:
In 60 seconds, the hand sweeps out a full circle of radius 14. The area of this circle is
A = pi*r^2 = pi*14^2 = 196pi
Half of this is what the hand sweeps out in 30 seconds, so A/2 = (196pi)/2 = 98pi is the exact area it sweeps out. Your calculator would then show 98pi = 307.8760800518 approximately
If instead you use pi = 3.14, then the approximate area is 98*3.14 = 307.72
