The missing dimension, x, is 7.5.
if you take 45 and divide it by 6 you can get the next dimension needed to get the full number, 45. You can also find it by dividing 35 and 4. I hope this helps.
Well there both even numbers so the gcf factor would have to be even also
60 = 1,2,3,4,5,6,10,12,15,20,30,60
72 = 1,2,3,4,6,8,9,12,18,24,36,72
The Gcf would be 12
