A ratio is a comparison between to values. For example, a solution containing 9 units of salt in 100 units of water has a ratio of 9:100, and a solution of 30 units of alcohol in 100 units of water has an alcohol to water ratio of 30:100. Percentages are also ratios, when the values are expressed out of a total of 100. The term "percent" literally means "per one hundred." Converting from ratio strength to percentage strength is straightforward, but a calculator is required.

Reduce the strength ratio to the lowest common denominator. For example 10:200 can be reduced to 1:20.

Divide 100 by the second number in the ratio. The result is the percentage value of each unit in the solution.

For example the ratio 1:20, contains 20 units. The percentage value of each unit is 100 / 20, or 5.

Multiply the first number in the ratio by the result from Step 2. The result is the strength of the solution expressed as a percentage.

For example, the percentage strength of a 1:20 ratio is 5 per cent because 1 x 5 = 5.

#### Tip

Use an online ratio to percentage calculator to simplify the process. The percentage strength of a solution is the same is the number of grams per 100ml.

#### Tips and warnings

- Use an online ratio to percentage calculator to simplify the process.
- The percentage strength of a solution is the same is the number of grams per 100ml.

#### References

- New Mexico State University College of Agricultural, Consumer and Environmental Sciences: A Ratio Is A Comparison Of Two Numbers
- College Of The Sequoias - Mathematics / Engineering Division: Solving Percent Problems Using Proportions
- Syracuse University Office of Institutional Research And Assessment: Review of Percents
- Santa Rosa Junior College; Chapter 9: Percentage, Ratio Strength, and Other Expressions of Concentration; Audrey C. White
- Mercer County Community College; The Relationship Among Fractions, Decimals, Percents; Debbie Kell
- University Of Detroit Mercy - College Of Health Professions: Mathematics Review for Anesthetists