Microsoft Excel help, converting to dates?

Alright, i am not new to Excel. I would consider myself an advanced user i guess. But, i am having the same problem I have been for a while, the same with other people.

When i copy and paste a spreadsheet into excel that has a slash, example 7/1, excel automatically changes it to a date. This does not help me if i am not working with dates. How do i stop excel from changing anything unless it is a formula? If i made the cells text based, i would not be able to add formulas. Changing the entire spreadsheet to text, then changing the unused cells to general is time consuming.

Adding ' in front of the cells also is out of the question when pasting hundreds to thousands of numbers each time.
It represents 2 numbers inside of one block. Not a fraction, but just two whole numbers, seperated by a /. Its how this database functions, i do not put in the numbers or choose what symbols to use. I wish it was something different.