using System.Collections.Generic;
public static void Main()
var inputs = new List<double> { 1.231d, 1.232d, 1.233d, 1.234d, 1.235d, 1.236d, 1.237d, 1.238d, 1.239d };
foreach(var val in inputs){
var floor2dp = Math.Floor(val * 100) / 100;
var round2dp = Math.Round(val, 2);
Console.WriteLine(string.Format("input: {0}, 2dp floor: {1}, round: {2}", val, floor2dp, round2dp));