Percentage calculation

Using Math.Round():

int percentComplete = (int)Math.Round((double)(100 * complete) / total);

or manually rounding:

int percentComplete = (int)(0.5f + ((100f * complete) / total));

(current / maximum) * 100. In your case, (2 / 10) * 100.

With C# String formatting you can avoid the multiplication by 100 as it will make the code shorter and cleaner especially because of less brackets and also the rounding up code can be avoided.

(current / maximum).ToString("0.00%");

// Output - 16.67%

Mathematically, to get percentage from two numbers:

percentage = (yourNumber / totalNumber) * 100;

And also, to calculate from a percentage :

number = (percentage / 100) * totalNumber;