Well to find the answer you would need to find the area of both. The area of a rectangle is base times height. 15*15= 225 so the area of the square pizza is 225. To find the area of a circle you do pi times radius squared. Radius is half of the diameter so the formula is pi(8^2). 8 squared is 64. Then you do 64 times pi. That equals 201 when rounded to the nearest whole number. That means the square pizza gives 24 inches more of pizza then the round one.