21. The diagram shows a circle of radius 1 contained in a square. If the area of the circle equals x% of the area of the square, then what is x rounded to the nearest integer?
x = 72.
It is incorrect.
Area of square with a side of 2r = 2(1) = 2 = 2^2 = 4
Area of circle = pi ( 1)^2 = pi
x = pi / 4 ≈ .79 = 79%
+589 
