Significant figures

Definition

Significant figures are the digits in a number that contribute to its precision, including all non-zero digits, zeroes between significant digits, and trailing zeroes in a decimal number. They indicate the accuracy of measurements and calculations.

5 Must Know Facts For Your Next Test

1. Non-zero digits are always considered significant.
2. Any zeros between significant figures are also significant.
3. Leading zeros are not considered significant as they only serve as placeholders.
4. Trailing zeros in a decimal number are significant because they indicate precision.
5. When performing calculations, the result should be rounded to the least number of significant figures in any of the numbers involved.

Review Questions

• How many significant figures are there in the measurement 0.00450?
• Why are trailing zeros after a decimal point considered significant?
• What is the rule for determining the number of significant figures when multiplying or dividing measurements?

Related terms

Precision: The degree to which repeated measurements under unchanged conditions show the same results.

Accuracy: How close a measured value is to the true value.

Rounding: Adjusting a numerical value to fewer digits, often based on specific rules related to significant figures.