Significant Figures

This statistical vignette was developed by Diana Garcia Silva, Michelle Weirathmueller, Steve Juliano, and Dax Soule


Significant figures are used in everyday measurements, where accurate values are needed to provide concise quantitative answers. Measuring devices such as rulers, calculators or thermometers all have limits to their precision, thus all numerical values are only as accurate as the measurement tool used to collect the data. This vignette will reinforce or establish a student's understanding of significant figures and how the "Atlantic-Pacific Rule" (Stone 1989) can be applied for any given measurement or mathematical operation.

Learning Objectives

  • Apply the rules of significant figures for a measurement
  • Express numerical values with the correct number of significant figures using a mnemonic device (the "Atlantic Pacific Rule")
  • Determine the number of significant figures from a given value or mathematical operation

Context for Use

This vignette can be used in either a single lab or lecture session and should take between 15 and 20 minutes for introductory or intermediate level students.

The vignette could be utilized in a variety of modules, where measurement of precise numerical values is needed to represent accurate values, such as Gross Primary Production rates in the Lake Metabolism module, heat budget and rates of change in the Lake Ice Phenology Module, flood frequency for Stream Discharge, and calculating probability of occurrence in the Water Quality Module.

Suggested Modules

Lake MetabolismLake Ice PhenologyStream DischargeWater Quality

Description and Materials

View the PowerPoint file and the instructor notes to help engage students during the presentation of the vignette.

StatVignette03_Sig.Figs_v04_07_15_2020.pptx (PowerPoint 2007 (.pptx) 4.9MB Sep21 20)

Click to view


Chang, R and Goldsby, K. (2013). Chemistry. 11th ed. McGraw-Hill Education, pp.19-23.

Stone, Helen M. Atlantic-Pacific sig figs. Journal of Chemical Education 66.10 (1989): 829.