Powershell: convert a fraction to an integer - surprising rounding behavior

Question

I have a interesting question on ints with decimals.

Assuming I do the following:

[int] $a = 5/2
$a

I\'ve tried it 10 times to be

Answer 1

[Math]::Floor($a) --> 2
[Math]::Ceiling($a)--> 3
[Math]::Round($a) --> 2

Floor will give you the preceding whole number and Ceiling will be providing the succeeding whole number. But if you want to round it up, using the Round function, it will follow midpoint rounding (Rounding at midpoint is historically away from zero), as demonstrated below -

[Math]::Round(2.50) --> 2
[Math]::Round(2.51) --> 3
[Math]::Round(2.49) --> 2
[math]::Round(2.50,[System.MidpointRounding]::AwayFromZero) --> 3
[math]::Round(2.49,[System.MidpointRounding]::AwayFromZero) --> 2
[math]::Round(2.51,[System.MidpointRounding]::AwayFromZero) --> 3

You can use either functions depending upon your requirement.