tested and worked.
add 2 more numbers in there:
If Note = 1,2,3,4,5, 6,23, or 24, I want to sum a field called PlateNumbers.
I tried:
Sum(IIf((Note >=1 And Note <=6) and (Note >=23 and Note<=24), PlateNumber, 0))
but that didn't work (I think this is a case of I can't see the forest...