That may be slightly more complicated than that. IEEE Standard rounding rules are somewhat unexpected to many people. This is what true rounding is supposed to be according to IEEE: 
$ perl -e 'my $c = 0.5; $c +=1 and printf "%f -> %0.0f\n", $c, $c for 
+1..10;'
1.500000 -> 2
2.500000 -> 2
3.500000 -> 4
4.500000 -> 4
5.500000 -> 6
6.500000 -> 6
7.500000 -> 8
8.500000 -> 8
9.500000 -> 10
10.500000 -> 10

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Round up if the previous digit is odd and round down if it is even.

Je suis Charlie.

In reply to Re^3: Decimal numbers calculations done inconsistently: Odd behavior! by Laurent_R
in thread Decimal numbers calculations done inconsistently: Odd behavior! by ferdi

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