Which has the greatest enclosed area, a rectangular corral with a perimeter p or a circular corral with a circumference p? recall that the circumference of a circle is the distance around the circle?

The area of a rectangle is equal to length times width in which the perimeter is equal to 2 times the sum of length and width. A circle's circumference is equal to 2pi*r. Area of circle is pi*r^2.    In this case, 

Rectangle A: A= lw = l*(p/2 - l)
Circle: A = pi*r^2 = pr/2

let as say r = l , then A of the circle is greater.