Is this something in common? Calc and system time?

[AG <computing.account@googlemail.com>]

On my partner's Lenny machine, her OOo Calc seems to round numbers or 
otherwise corrupt the numbers in the cells.  Her machine is also 
notorious for losing time and fixating on being in the time zone of 
Guernsey (not London).

For example, the following numbers in her Calc add up differently than 
on mine:
11.73 + 7 + 15.75 + 24.68 + 17.5 + 21.18 + 20.65 + 17.85 + 19.25 + 23.1 
+ 12.6 + 10.5 + 23.8

This should equate to 225.59 but on her machine was coming to 225.58

Not a biggie, but rolling errors can cause havoc, and anyway doesn't 
inspire confidence when dealing with finances, etc.

Are these likely to be connected, and if not, then what gives with Calc?

Thanks for any help.

AG