(Sort)Rounding Magic - C#, C#

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//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

/*
Rounding functions to Round a decimal number to nearest 0.5, 0.25, 2
These can be used in Ranking or Rating system
Example: 
 1.0 should be equal to 1. Similarly, 1.1 = 1, 1.2 = 1, 1.3 = 1.5, 1.4 = 1.5... 1.8 = 2 and so on while Rounding to nearest one-half (0.5)
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            for(decimal i=1;i<=2;i+=0.1m)
                Console.WriteLine("{0}, NearestOneHalf: {1}",i,NearestOneHalf(i));
            
            Console.WriteLine("");
            for(decimal i=1;i<=3;i+=0.1m)
                Console.WriteLine("{0}, NearestTwo: {1}",i,NearestTwo(i));
            
            Console.WriteLine("");
            for(decimal i=1;i<=3;i+=0.1m)
                Console.WriteLine("{0}, Nearest Quarter: {1}",i,NearestQuarter(i));
        }
        
        //Round to nearest 0.5
        public static decimal NearestOneHalf(decimal d)
        {
            decimal d1 = d*2;
            decimal d2 = Math.Round(d1,MidpointRounding.AwayFromZero);
            decimal d3 = d2/2;
            return d3;
        }
        
        //Round to a number nearest to a multiple of 2
        public static decimal NearestTwo(decimal d)
        {
            decimal d1 = (d/2)*2;
            decimal d2 = Math.Round(d1,MidpointRounding.AwayFromZero);
            return d2;
        }
        
        //Round to a number nearest to Quarter .25
        public static decimal NearestQuarter(decimal d)
        {
            decimal d1 = d*4;
            decimal d2 = Math.Round(d1,MidpointRounding.AwayFromZero);
            decimal d3 = d2/4;
            return d3;
        }
    }
}

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Compilation time: 0,16 sec, absolute running time: 0,11 sec, cpu time: 0,09 sec, average memory usage: 16 Mb, average nr of threads: 3