The following codes explain the rounding operation in Decimal types.
The "#" symbol defines the rounding value here.

Example 1:

Rounding for 4

using System;
using System.Text;

namespace forgetCode
{

   class program
    {        
        public static void Main()
        {
            decimal[] decimalNumbers = {6.12347654333M,4.34446M};

            foreach (decimal decimalNumber in decimalNumbers)
            {
                Console.WriteLine("Original Decimal Number = {0}, Without Zeros = {1}",
                                    decimalNumber, decimalNumber.ToString("0.####"));
            }
        }
    }
}

Output:
Original Decimal Number = 6.12347654333, Without Zeros = 6.1235
Original Decimal Number = 4.34446, Without Zeros = 4.3445

Example 2:

Rounding for 2

using System;
using System.Text;

namespace forgetCode
{

   class program
    {        
        public static void Main()
        {
            decimal[] decimalNumbers = {6.12347654333M,4.34446M};

            foreach (decimal decimalNumber in decimalNumbers)
            {
                Console.WriteLine("Original Decimal Number = {0}, Without Zeros = {1}",
                                    decimalNumber, decimalNumber.ToString("0.##"));
            }
        }
    }
}

Output:

Original Decimal Number = 6.12347654333, Without Zeros = 6.12
Original Decimal Number = 4.34446, Without Zeros = 4.34