If the percent of discount of an item is 64% and the sale price is $72 then what is the original price?

We can use porpotion to get the answer
72 is 100%-64%=36%
36% 72
100% x
crossmultiply
36x=100*72
36x=7200           /:36
x=7200:36
x=200 - its the answer

Where’s the problems ? ?