Output c#

Question

I saw this code on c# interview questions.
I thought the output will be 7 and 12 but the truth is the output will be 6 and 12. Why is that?

public class Program
{
public static void Main(string[] args)
{
Console.WriteLine(Math.Round(6.5));
Console.WriteLine(Math.Round(11.5));
}
}

Answer 1

Math.round (c#) runs on something called bankers rounding:
"The integer nearest a. If the fractional component of a is halfway between two integers, one of which is even and the other odd, then the even number is returned."