I have entries in col G, formatted as General, containing text like the
following. (They represent the sizes of files. Only GB or MB. Always
three digits.)

Col G (text)
-------
3.40 GB
3.82 GB
22.8 MB


I want to place a formula or function or macro in col H which converts
col G to GB. (So that I can subsequently do addition on selected cells,
working only in GB.)

Col H (GB, numbers to 3 dp)
------
3.400
3.820
0.023

Struggling here, particularly with stripping out the GB or MP suffices,
so would much appreciate some help please.

Terry, East Grinstead, UK