How do I format to only include decimal if there are any

Question

What is the best way to format a decimal if I only want decimal displayed if it is not an integer.

Eg:

decimal amount = 1000M
decimal vat = 12.50M

When formatted I want:

Amount: 1000 (not 1000.0000)
Vat: 12.5 (not 12.50)

Answer 1

    decimal one = 1000M;
    decimal two = 12.5M;

    Console.WriteLine(one.ToString("0.##"));
    Console.WriteLine(two.ToString("0.##"));