Topic summary · IGCSE handout
Decimals summary
Decimals connect place value to fractions and percentages. Accuracy of rounding and careful column arithmetic matter in exams.
Files: 9_decimals_handout.pdf · 9_decimals_handout_answers.pdf · free public downloads · diagrams in the PDFs
Key learning points
- Ordering decimals: compare digit-by-digit from the tenths place.
- Multiplying/dividing by powers of 10 shifts the point.
- Rounding: look one digit beyond the place required.
Worked example 1 — Ordering
Order from smallest to largest.
Working
Compare digit-by-digit from the tenths place.
Worked example 2 — Rounding
Round to 2 decimal places.
Working
The third decimal digit is 6, so round up.
Worked example 3 — Multiply by powers of 10
Calculate .
Working
Move the point two places right.
Worked example 4 — Divide by powers of 10
Calculate .
Working
Move the point three places left.
Scaffolded Learning Sheet and answers (PDFs)
This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.
