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Percent Deviation Calculator Formula

Percent Deviation Formula:

\[ \% \text{ Deviation } = \frac{|\text{Measured} - \text{Expected}|}{\text{Expected}} \times 100 \]

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1. What Is Percent Deviation?

Percent deviation is a statistical measure that quantifies the difference between an observed (measured) value and an expected (theoretical) value, expressed as a percentage of the expected value. It helps assess the accuracy and precision of measurements.

2. How Does The Calculator Work?

The calculator uses the percent deviation formula:

\[ \% \text{ Deviation } = \frac{|\text{Measured} - \text{Expected}|}{\text{Expected}} \times 100 \]

Where:

Explanation: The formula calculates the absolute difference between measured and expected values, divides by the expected value, and multiplies by 100 to convert to percentage.

3. Importance Of Percent Deviation Calculation

Details: Percent deviation is crucial in quality control, scientific experiments, manufacturing processes, and data analysis to evaluate measurement accuracy, identify errors, and ensure consistency in results.

4. Using The Calculator

Tips: Enter both measured and expected values. The expected value cannot be zero. Results are displayed as percentage deviation with two decimal places precision.

5. Frequently Asked Questions (FAQ)

Q1: What does a high percent deviation indicate?
A: A high percent deviation suggests significant difference between measured and expected values, which may indicate measurement errors, experimental variability, or process inconsistencies.

Q2: What is considered an acceptable percent deviation?
A: Acceptable deviation varies by industry and application. Typically, lower values (0-5%) indicate good accuracy, while higher values may require investigation.

Q3: How is percent deviation different from percent error?
A: Percent deviation and percent error are often used interchangeably, though some contexts use percent error specifically for comparison to known standards.

Q4: Can percent deviation be negative?
A: No, because the formula uses absolute value, percent deviation is always a positive number or zero.

Q5: When should I use percent deviation?
A: Use it when comparing experimental results to theoretical values, assessing measurement accuracy, or evaluating quality control in manufacturing processes.

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