Practice questions
Challenge questions
Round to multiple degrees of s.f. and explain the effect; use s.f. in context
Word problems
Real-life contexts — read carefully
What is a significant figure?
Significant figures are counted from the first non-zero digit.
\(3{,}472\) to 1 s.f. = \(3{,}000\) · \(3{,}472\) to 2 s.f. = \(3{,}500\) · \(3{,}472\) to 3 s.f. = \(3{,}470\)
\(0.00382\) to 1 s.f. = \(0.004\) — the zeros before the 3 are not significant.
Same rule: look at the next digit. ≥5 → round up. <5 → round down.