using System;

using System.Text.RegularExpressions;                   

​

public class Program

{

    public static void Main()

    {

        string[] spacing = (Regex.Split("aaa 1.50 X bbb 2.50", @"\s*[x/*X]\s*"));

        Console.WriteLine(Regex.Replace(spacing[0], "[^0-9.]",  ""));

        Console.WriteLine(Regex.Replace(spacing[1], "[^0-9.]",  ""));

    }

}