Fist add 203 and 220 and you get 423. Then add all the dvds 11+3 and you get 14 then Next add all the video games 11+14 and you get 25 next divide 25 from 423 then you get 16.92 then divide the dvds 423 divided by 14 and you get 30.21
The largest square piece will be the largest factor between 24 and 18. This means the largest number that divides into 24 and 18. This number is 6. So each piece will be 6 inches by 6 inches.