Changing a cell value by a percentage in the same cell in multiple worksheets

I would like to update my prices in a workbook with multiple worksheets.

So I want to increase cell g12 by 5% and have that value put in cell g12
and I would like it to do that on all worksheets.

How would I do that without having to do manual calculations for each worksheets.
Is there a macro I could do that would change each sheet?