By using the Paste Special Add feature.

Type 10 in a cell of to the side somewhere. Copy that cell. Highlight the
cells you want to increase by 10, right click to get the shortcut menu,
choose Paste Special, select Values and Add, clidk OK. Delete the 10 you
typed.

Good luck.
Erin

"Basikstylz" wrote:

I have a spreadsheet which has cells that I have already filled several cells
with numbers. Now I need to increase the cells by the same amount, say 10.
how can I increase all the cells without having to key them by hand?