|Read up on VLOOKUP in the Excel Help files.|
You would set up a table that had the list of dropdown choices in the 1st column and your associated "decimal numbers" in another. You would probably want to use the same 1st column list to create the drop down list to ensure an exact match every time.
VLOOKUP would look up the text chosen in the drop down and return the associated value.
This could also be done with an IF statement, but VLOOKUP might be much more efficient depending on how many choices you had. Editing the table as dropdown choices and/or values change is a lot easier then editing the formula.
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