Adding numbers in the same cell

how can I take a number from one cell and add it to a number from another cell and keep the answer in the same cell

THANKS RICHARD!

You are describing an accumulator. Say you enter 4 in A1 and A2 becomes 4. If you now enter 7 in A1, A2 becomes 11. If you then enter 9 in A1, A2 becomes 20.

You can set this up with a macro.
Is this what you want?

Hi,

I find it difficult to visualise what you describe. Can you give some specific examples please?

Hi,

Yes, you'd use a Sheet_Change macro to update the relevant line that contains the Quantity.
I suggest that you add a third helper cell which uses an =MATCH() function to identify which row of your table contains the Part # you enter (either directly or via a drop down containing all part numbers) and then use that helper cell in the macro.

Untested since I don't have direct access to Excel at the moment - but assuming the part numbers are all in column A, with quantities in Column B, the part number in say D1 and the Quantity to adjust in E1, with a helper cell in F1 which contains the function

Formula:

=MATCH(D1,A:A,False)

Name the helper cell say "UpdateRow"

Now the macro would be

Sub Worksheet_Change(ByVal Target As Range)
   If Not Intersect (Target, Range("E1")) Is Nothing Then
      Range("B" & Range("UpdateRow"))=Range("B" & Range("UpdateRow"))+Range("E1")
   End If
End Sub

Hi,

You would need to use a macro. Something like

Range("A2") = Range("A2")+Range("A1")