I'm beginner in Arcgis, so sorry if this theme is not appropriate for this forum. My question is quite simple. I wanna create a buffer with more 20% of the area of a polygon that already exist. This extra area will surround my polygon. I've just found in help how to create a buffer by distance. But my problem is that I don't know what is the linear distance I must add to my polygon that will add 20% of it's area... Can someone help me?