using System;

public class Program

{

    public static void Main()

    {

        var current = 13m;

        var total = 17m;

        //

        var first = 12m;

        var second = 5m;

        //

        var firstResult = current * (first / total);

        var secondResult = current * (second / total);

        var firstTruncated = firstResult - Math.Truncate(firstResult);

        var secondTruncated = secondResult - Math.Truncate(secondResult);

        Console.WriteLine(firstResult);

        Console.WriteLine(secondResult);

        Console.WriteLine(firstTruncated + secondTruncated);

        Console.WriteLine(firstResult + secondResult);

    }

}