1. Significant Figures How to count the number of significant figures in a decimal number. How to count the number of significant figures in a decimal number. Zeros Between other non-zero digits are significant. a. 50.3 has three significant figures b. 3.0025 has five significant figures

2. Significant Figures Zeros in front of nonzero digits are not significant: 0.892 has three significant figures 0.0008 has one significant figure

3. Significant Figures Zeros that are at the end of a decimal number are significant. 57.00 has four significant figures 2.000000 has seven significant figures At the end of a non-decimal number they are not. 5700 has two significant figures 2020 has three significant figures

4. Non-Decimal Numbers Major pain to try to figure out the significant figures – it depends on the number’s history. Don’t Use Them.

5. Practice Find the number of significant figures. 1. 2.00450 2..0034050 3. 1450 4. 0.02040 1. 6 sf’s. 2. 5 sf’s 3. 3 sf’s 4. 4 sf’s 1. 6 sf’s. 2. 5 sf’s 3. 3 sf’s 4. 4 sf’s

6. Significant Figures After Division and Multiplication After performing the calculation, note the factor that has the least number of sig figs. Round the product or quotient to this number of digits. 3.22 X 2.1 = 6.762  6.8 36.5/3.414 = 10.691  10.7

7. Significant Figures Addition or subtraction with significant figures: – The final answer should have the same number of digits to the right of the decimal as the measurement with the smallest number of digits to the right of the decimal. Ex: 97.3 + 5.85 = 103.15  103.2