Relative and Percentage Error

The exact value is $50$. An approximation gives $48$. Find the relative error and the percentage error.

• 1Absolute error: |$48-50$| = $2$
• 2Relative error: $2÷50=0.04$
• 3Percentage error: $0.04\times 100\%=4\%$

Answer: Relative error = $0.04$, Percentage error = $4\%$

The exact value is $8$. An approximation gives $8.5$. Find the percentage error.

• 1Absolute error: |$8.5-8$| = $0.5$
• 2Relative error: $0.5÷8=0.0625$
• 3Percentage error: $0.0625\times 100\%$

Answer: $6.25\%$