Rounding

Hi,
You do not realise my trepidation in asking this question for fear it is
supremely basic. Here goes...

If I ask Excel to ROUND(A1,0) , and 74.45 is in cell A1, why does it not
round to 75.0?

I have a grade that only kicks in at 75%(B grade). A student who gets
74.45% will not be awarded this grade but the one below. The cell is
formatted to show as 74.5, and it does not show up as a B but a C.

74.45, 74.46, 74.47, 74.48, 74.49 will all return 74 after ROUND(A1,0).
Intuitively I...

Rounding