Signifigant Figures

Digits with known certainty and the first uncertain or estimated digit

The known digits come from the measuring device, The final uncertain digit is estimated according to the markings on the measuring device

• The decimal place you estimate is the last significant figure

Scientific notation

If the measurement is in scientific notation, All given digits are significant

Standard notation Rules

• All nonzero digits are significant

• captive/embedded zeros are significant

• leading zeros are not significant

• Trailing zeros are only significant if the number has a decimal

If the number has a decimal point, count from right to left until you hit the last nonzero digit

If the number does not have a decimal, count the digits from left to right until you reach a trailing zero

Calculations

Determine the proper number of significant figures and round l and add zeros until it has the right number

• Depends on the type of operation

• 5 or higher up

• 4 or lower - no change

Addition and Subtraction

only concerned with the number of decimal places

• Sig. figs. is controlled by the measurement with the fewest decimal places

Multiplication and Division

The answer must have the same number of Sig. figs. as the Measurement with the fewest Sig figs

• quantities you can count and exact conversion factors have unlimited Sig figs