If the content of cell A1 is CDB1002, you can enter this formula in cell B1:

="205"&A1

With cell B1 selected you can Shift-click cell B3000 to select the whole
range. Now you can press Ctrl+D to copy the formula of the top cell of the
selection and paste it into the rest of the selected cells.

If you want to delete the cells with the original numbers (in column A), you
have to select the cells with the new numbers (in column B) and drag the
frame with the right mouse button to a new column, e.g. column C, and then
select "Copy Here as Values Only". Then delete columns A and B.

--
Kristoffer Andreas Berg
Programmer on a hobby basis
http://home.online.no/~gunnarab


"jgately" wrote:

Sure we have a group on 3000 serial numbers that were enter by using the
last 7 number and not all 10 . We are trying to determine if there is a
function that will allow us to add 205 to all the exsiting cells
Exisiting need to be
CDB1002 205CDB1002
CDB1003 205CDB1003
CDB1004 205CDB1004
<SNIP