Use a Vlookup formula in cell H11.

You will need to set up a lookup table but if your data validation is
using a list from a spreadsheet then you are already half way there.
Next to your list of codes that appear in the dropdown enter the number
you want to appear in H11 associated with each code.

Say this table is in range A1:A10.
In H11 enter the formula
=vlookup(G11,A1:A10,1,0)

For more detail on vlookups see excel help and
http://www.contextures.com/xlFunctions02.html

Hope this helps
Rowan

JerseyBoy wrote:
I am hoping someone can help me with this.

I used the DataValidationList function in a particular cell in my
spreadsheet.
Once that cell returns a particular entry, I want an adjacent cell to
populate with the corresponding number.

For example. I have a "drop down box" in cell G11. I click on the drop down
box and choose option WM6023. Once I have chosen that I want the adjacent
cell (H11) to recognize that entry and populate with the number 709. i.e.
the number 709 will always be associated with "WM6023" and will automatically
populate in cell H11 when "WM6023" is chosen from the "dropdown box" in G11.
It also follows that If I choose another entry from the "dropdown box" in
G11 a different cooresponding number will appear in H11.

Any ideas?