Yes, type your entry into the first cell (E4) and then select all 3 cells,
use Format | Cells | [Alignment] and in the Horizontal alignment selection
you can choose Center Across Selection.
My apology - I misread things - I realize you're looking for VERTICAL
centering, not horizontal centering. For that you would need to merge the
cells involved and then choose the Cell | Format | Alignment and center
vertically.
Having difficulty viewing things in IE browser today, so if this is a repeat
answer, again my apologies, I can't even see my original reply at the moment.
It's easy, all you have to do is highlight the cells you want centered, then
right click and select "Format Cells" then select the "Allignment" tab select
the drop down box for either Horizontal or Verticle and select center.
After spending too much time looking for a solution to this and not finding one I eventually just set the text colour of the other items to white then put the border around the selection. You leave one item in black and it'll be in the center if you have an odd number of cells otherwise it will just have to be a bit off center.