What is 1/5 represented as a percentage?

To convert a fraction to a percentage, you can multiply the fraction by 100. In the case of 1/5, you start by performing the division, which gives you 0.2. Multiplying 0.2 by 100 results in 20%. This means that 1/5 is equivalent to 20 out of 100, or 20%.

This explanation underlines why 20% is the correct answer. Understanding this process of converting fractions to percentages is crucial in pharmacy calculations, as it helps in interpreting dosages and medication concentrations accurately.