Answer: Approximately 5.22%
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Work Shown:
A = true value = 13.4 seconds
B = measured value (erroneous value) = 14.1 seconds
C = percent error
C = [ (B-A)/A ] * 100%
C = [ (14.1-13.4)/(13.4) ] * 100%
C = 0.0522 * 100%
C = 5.22%
This value is approximate.