Question

How would I write the data as ordered pairs? Would it be (1,31), (3,34)… ect?
U.S size
1 , 3, 5, 7, 9, 11
European size
31, 34, 36, 39, 41, 44

Answer 1

that's the way I'd do it.
Of course, the reverse ordering would also be a way to do it.

Your way gives you the European size for a given US size.

Answer 2

Ok thank you kindly!!