RULES FOR SIGNIFICANT FIGURES:

• All non-zero digits are significant.
• Zeros between any numbers are significant.
• Trailing zeros in numbers without decimal are not significant.
• Trailing zeros to the right in the numbers with decimal are significant.
• Leading zero is not significant.

Simple Examples:

2500

2 sig figs

$$2.5 * 10^3$$

2500.

4 sig figs

$$2.500 * 10^3$$

0.025

2 sig figs

$$2.5 * 10^-2$$

0.0250

3 sig figs

$$2.5 * 10^-2$$

Addition Examples:

$$2.47\;+\;1.2\;=\;3.67$$

$$=\;3.7$$

Multiplication Examples:

$$1.69m \;*\;2.09 m \;= \;3.5321 m^2$$

$$3.53 m^2$$