Understanding Approximation and Errors

What is the formula to calculate percentage error?

• (Actual Value - Estimated Value) * 100

• (Estimated Value + Actual Value) / 2

• (Estimated Value / Actual Value) * 100

• (|Estimated Value - Actual Value| / |Actual Value|) * 100

If a measurement is 50 and the true value is 52, what is the percentage error?

• 4.00%

• 5.00%

• 3.85%

• 2.50%

How many significant figures are in the number 0.00456?

• 3

• 5

• 4

• 2

Round the number 123.456 to two decimal places.

• 123.46

• 123.50

• 123.45

• 124.00

What is absolute error?

• Absolute error is calculated as measured value + true value.

• Absolute error is the average of all measured values.

• Absolute error is calculated as |measured value - true value|.

• Absolute error is the difference between two measured values.

If the measured value is 10 and the true value is 12, what is the absolute error?

• 1

• 3

• 5

• 2

Define relative error in your own words.

• Relative error is the difference between the measured value and the true value.

• Relative error is the total error in a measurement without reference to the true value.

• Relative error is the average of all errors in a set of measurements.

• Relative error is the ratio of the absolute error to the true value, often expressed as a percentage.

If the absolute error is 2 and the true value is 10, what is the relative error?

• 0.1

• 0.2

• 1.0

• 0.5

How do you determine the number of significant figures in a measurement?

• Count all non-zero digits, zeros between them, and trailing zeros in decimal numbers.

• Ignore all zeros in the measurement.

• Count only the non-zero digits.

• Only consider the first three digits.

Round the number 987.6543 to the nearest whole number.

• 990

• 988.5

• 987

• 988