Numbers — Significant Figures

Only the digits left of the decimal point

Digits that contribute to the precision of the measurement

All zeros in the number are always significant

Digits chosen by rounding to nearest ten

4

3

2

5

With as many digits as possible without rounding

Always round to three significant figures

With the same number of significant figures as the least precise factor

Match the number of decimal places of the largest operand

Always truncate instead of rounding to avoid bias

Convert to fractions to avoid any rounding

Round after every operation to the current significant figures

Keep extra digits through intermediate steps, round only final result

Count them only if the number is even

Ambiguous; without a decimal they may be placeholders and not necessarily significant

Always count all trailing zeros as significant

Never count trailing zeros as significant

Maintain full precision of both operands

Three significant figures regardless of decimals

Three decimal places, matching the least decimal precision

Round to the larger number's decimal places only

It clearly shows which digits are significant and avoids ambiguity with zeros

It's only useful for very small numbers

It eliminates the need for rounding

It always increases the number of significant figures

Treating a calculated exact constant as measured and giving it unnecessary sig figs

Believing significant figures apply only to integers

Always matching the calculator display precision

Assuming more significant figures always improve accuracy