using System;

using System.IO;

public class Program

{

    public static void Main()

    {

        using (StreamWriter WriteNum = new StreamWriter("Number_File.txt"))

            {

            WriteNum.WriteLine("100");

            WriteNum.WriteLine("25");

            WriteNum.WriteLine("30");

            WriteNum.WriteLine("75");

            }

        using (StreamReader readNum = new StreamReader("Number_File.Txt"))

        {

          string numLine;

              while ((numLine = readNum.ReadLine()) != null )

                {

                  if (Convert.ToUInt16(numLine) > 50 )

                  {

                    Console.WriteLine(numLine);

                  }

               }

        }

    }

}

​

​