Wellcome all!

I'm writting the software for invoicing. Essential to this is to use mathematical rounding to two decimal places.

I've tried to use:
Qt Code: 
  1. QString::number(value,'f',2).toDouble();
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but - it doesne't work!

for example:
2582.3250 return me: 2582.32 -it's wrong! It should be 2582.33

what am I doing wrong?