VCE · Topic explainer
How do you round to significant figures?
Count significant figures from the first non-zero digit. Keep the requested number of digits, then round up if the next digit is 5 or higher. Leading zeros locate the decimal point. Zeros between significant digits count, and trailing zeros after a decimal point can show precision. Round at the end of a multi-step calculation.
Worked example
A volume calculation gives 0.003846 m³. The first three significant digits are 3, 8 and 4. The following digit is 6, so the three-significant-figure result is 0.00385 m³.
In scientific notation the same result is 3.85 × 10⁻³ m³. The power of ten gives the size of the measurement and the coefficient shows the three significant digits.
Official exam practice
Find other years and marking guidance in the Foundation Mathematics official exam archive.