How to have an entry mean another value on another sheet

Hi, Being self taught excel I am setting up my worksheet but cannot create an equation to get the correct answer. I wish to enter in a cell a number or a letter that will represent a costing value, that appears as this value correctly on another sheet i.e.
Sheet 1 Cell A2 1,2,3 or a,b,c etc to appear on
Sheet 2 Cell A2 as 30, 27.5, 25 etc

As I am setting up a pricing sheet I do not want the user to know the discount percentage.

I have played with "If" etc but get stuck due to wishing to have 9 referencing values. Multiplication does not work. Can anyone help please?