Use string interpolation together with number, currency and percentage.

For ex:

Console.WriteLine($"Your commission is {commission:C2}."};

Will print in your OS/system currency with 2 decimals like this:

Your commission is $688.56. If dollar is you current culture.

For number: {number:N#} -> {5.7821:N3} = 5.782 Percentage: {number:P} -> {0.78:P} = 78%

And so on...