Maths Dictionary · JSS 2
Significant figures (s.f.)
Simple meaning
The important digits of a number, counted from the first non-zero digit.
Example
0.004872 to 2 s.f. is 0.0049.
See it
From the Significant Figures lesson. Try moving things around.
45,678
■ keep · ■ deciding digit · ■ not counted / dropped
Next digit is 6 → 5 or more: round UP45,678 ≈ 46,000 (2 s.f.)
Significant figures
2