## Percent Error

Use when comparing a theoretical (known) value to an experimental (measured) value.

Percent Error =

abs(Experimental Value - Theoretical Value)abs(Theoretical Value)

x 100%

(where abs = absolute value)

(Enter values into the blue boxes. Answer will appear in the black box.)

Answers are rounded to 7 decimal places.

## Examples

Example 1:

A measured value is 45.6

The actual value is 46.0

What is the percent error between the measured and actual values?

Theoretical (actual) Value = 46.0

Experimental (measured) Value = 45.7

Percent Error = 0.65%

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Example 2:

An estimate is made and its value is 115

The actual value is 95

What is the percent error between the estimate and actual value?

Theoretical (actual) Value = 95

Experimental (estimated) Value = 115

Percent Error = 21%

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Example 3:

The number 2.7 has been rounded up to 3

What is the percent error between the rounded number and the actual number?

Theoretical (actual) Value = 2.7

Experimental (rounded) Value = 3

Percent Error = 11%

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