<h3>Answer: 40%</h3>
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Work Shown:
Subtract the values to get 2.1-1.5 = 0.6
Brianna is off by 0.6 liters
Divide that error by the true value 1.5 to get 0.6/1.5 = 0.40
Then move the decimal point 2 spots to the right to arrive at 40%
Therefore, the percent error is 40%
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The formula you can apply is:
where
P = percent error
G = guess value (in this case it is 2.1)
T = true value (which is 1.5 in this case)
If we were to apply the formula, then we get: