A percentage is a fraction, where the denominator is always equal to 100. So 5% is equal to:
[tex]\frac{5}{100}[/tex]If we multiply this fraction with the value, we should be able to determine how much of that value is equal to 5%.
[tex]\frac{5}{100}\cdot321=\frac{1605}{100}=16.05[/tex]The result is 16.05.