Area= length x width since its a square and squares have their lengths and widths the same, we will say that x represents length and width. so... area=x*x area=x^2 we know that the area of the pool is 183.84 square meters so plug that into area 183.84=x^2 solve for x by square rooting both sides you will get x=... (square root of 183.84) so that is x value is your width and length. therr are 4 sides on a square so multiple x by 4 to get perimeter.
The answer you seek you just need to take 325 and divide it by 500 to get .65 and change .65 to 65%. And to make sure you multiply 500 by .65 to get 325. Hope I helped