using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine((175.500000m).Truncate(0).ToString("F" + 2));

    }

}

​

public static class DecimalExtensions

{

    public static decimal Truncate(this decimal value, int decimalPlaces)

    {

        if (decimalPlaces is < 0 or > 6)

            throw new ArgumentOutOfRangeException(nameof(decimalPlaces), "Erro");

        else if (decimalPlaces == 0)

            return Math.Truncate(value);

        else

        {

            var integerPart = Math.Truncate(value);

            var scalingFactor = value - integerPart;

            var multiplier = (decimal)Math.Pow(10, decimalPlaces);

​

            scalingFactor = Math.Truncate(scalingFactor * multiplier) / multiplier;

​

            return integerPart + scalingFactor;

        }

    }

}