Question 1143604
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What shaded region...?<br>
Let r be the radius of the circle; then the side of the square is the diameter of the circle, which is 2r.<br>
area of square: {{{(2r)^2 = 4r^2}}}
area of circle: {{{(pi)r^2}}}<br>
P(penny lands inside the circle) = {{{pi/4}}}<br>
P(penny lands inside the square but outside the circle) = {{{(4-pi)/4}}}<br>
Use that to find the probability that the penny lies in your shaded region.