1. Significant Figure Rules

2. Rule Number 1 All non zero digits are significant. Examples 1179 – 4 significant figures 215 - 3 significant figures 17 - 2 significant figures

3. Rule Number 2 Zeros in between non zero digits ARE significant. Examples 203 - 3 significant figures 3005 – 4 significant figures

4. Rule Number 3 Zeros at the end of a number and to the right of a decimal ARE significant. Examples 10.00 – 4 significant figures 7.2 - 2 significant figures

5. Rule Number 4 Zeros in front of non zero digits are not significant. Examples.000257 – 3 significant figures.00257 - 3 significant figures

6. Rule Number 5 Zeros to the left of a decimal are confusing so scientific notation is used to tell the number of significant figures. Example 1000 = 1.00 x 10 3 (ALWAYS USE 3 SIGNIFICANT FIGURES)

7. Rule Number 6 A decimal point at the end of a “zeroed” number denotes an exact number. All digits are significant. Examples 10000. – 5 significant figures 100. – 3 significant figures 10. – 2 significant figures

8. Addition and Subtraction The answer cannot have any more place values to the right of the decimal than the least digits present in the problem. Example 10.52 – 7.3 = 3.2

9. Multiplication/Division The answer cannot have any more significant figures than the least number present in the problem. Example 10.52 / 7.3 – 2 significant figures

10. Multiplication/Division The number 1 (one) does not change significant figures on multiplication/division problems.