using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        List<short> resultTemp = new List<short> { 1,2,3,4,5,6,7,8,9 };

        var targetItemsCount = 5;

​

        var roundingError = resultTemp.Count % targetItemsCount;

        var reduceIndex   = (resultTemp.Count - roundingError) / targetItemsCount;

​

        List<short> result;

        if (reduceIndex <= 1)

                result = resultTemp.Take(targetItemsCount).ToList();

        else

            result = resultTemp.Where((a, index) => index % reduceIndex == 0).Take(targetItemsCount).ToList();

        foreach (short x in result)

        {

            Console.WriteLine(x);

        }

    }

}