Significant Figures

1. Non zero digits - non-zero numbers are significant

2. Zeros - There are three types:

a) Leading zeros are zeros that precede all non-zero digits. These zeros are not significant figures.

b) Captive zeros are zeros between sig. figs., usually non-zero digits. These zeros are significant figures.

c) Trailing zeros are zeros at the right end of the number. They are sig. figs. only if the number contains a decimal point.

3. Exact numbers are numbers that are derived by counting or by definition. These numbers have infinite number of sig. figs.

MULTIPLICATION AND DIVISION RULES

The number with the fewest sig. figs. in the calculation will limit your answer to that number of sig. figs.

ADDITION AND SUBTRACTION RULES

The number of sig. figs. in the calculation is limited to the number with the fewest number of decimal places to the right of the decimal point. If neither number has a decimal place, sig. figs. are stopped at the first break between sig. figs. and non - sig. figs. furthest from the right of the numbers.