Laboratory Formula
Coefficient of Variation Formula
Expresses variability relative to the mean as a percentage.
Formula Summary
Coefficient of Variation
Expresses variability relative to the mean as a percentage.
- Category
- Laboratory
- Equation
- CV = s ÷ x̄ × 100
- Calculator
- Use Coefficient of Variation Calculator →
Equation
CV = s ÷ x̄ × 100
Variables
- CV = coefficient of variation
- s = standard deviation
- x̄ = mean
How to Use This Formula
- Identify the known values from the problem statement.
- Convert all values into compatible units.
- Substitute the values into the equation and calculate the result.
- Check that the final answer has the correct unit and meaning.
Explanation
The coefficient of variation compares the standard deviation to the mean value and expresses variability as a percentage. It is useful for comparing the relative spread of different datasets.
Worked Example
If the standard deviation is 5 and the mean is 50, the coefficient of variation is (5 ÷ 50) × 100 = 10%.
Common Mistakes
- Using the wrong mean value.
- Forgetting to multiply by 100 to convert to percentage.
- Comparing datasets with inappropriate or zero means.
Applications
- Comparing precision between experiments.
- Analyzing variability in scientific measurements.
- Evaluating consistency of laboratory data.
Related Formulas
Sample Standard Deviation
s = √(Σ(xᵢ − x̄)² ÷ (n − 1))
Measures the spread of sample observations around their mean.
Learn formula →Percent Error
% error = |experimental − accepted| ÷ |accepted| × 100
Compares an experimental result with an accepted reference value.
Learn formula →Percent Difference
% difference = |A − B| ÷ ((|A| + |B|) ÷ 2) × 100
Compares two experimental values when neither is an accepted value.
Learn formula →