Significant figures rules revisited

Author: Ahmad Sattar

Significant figures rules revisited

In significant figures practice, 0s to the right of the sig figs are significant only if they are justified by the precision of their derivation. For instance when struck with the question as to how many significant figures are in the value 14.13000, you can conclusively demonstrate that it can have seven sig figs: 1, 4, 1, 3, 0, 0 and 0.

On the other hand, the number 0.0001324320 still has only seven significant figures (the 0s preceding figure 1 are not considered significant). In addition to that, 130.00 has 5 significant figures since it has 3 trailing 0s. 

The significance of trailing zeros in values not containing decimal points can come across as ambiguous. Consider this, for instance, it might not always be clear if a number, say, 1300, is precise to the closest unit or if it is only shown to the nearest hundred due to rounding or uncertainty. To round number to spacific digit then visit this link

Note: if numbers are in standard form then the same significant rules will also be applied to these numbers. visit our Standard Form Calculator.

Many methods exist to address this type of issue, but these approaches are typically esoteric and not quite understood by those who are not the specialists in this particular field.

An over-line, also known as an over-bar, or more roughly, a vinculum, can be placed over the last sig fig; any trailing zeros following this would not be considered significant. Suppose, a value, 1400 has three significant figures (and therefore, indicates that the value is precise to the closest ten).

Less frequently, employing an intimately related convention, the last significant figure of a numerical value can be underlined; for example, "3000" has two significant figures.

A decimal point can be placed after the number; for instance "200." indicates that 3 significant figures are meant.

When it comes to the combination of a number and a unit of measurement, you can avoid the ambiguity by choosing a reasonable unit prefix. For instance, the number of significant figures in a mass given as 1600 g is ambiguous, while if stated as 1.6 kg, it is not.

Sig Fig Calculator is worked on these rules.


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