Number 4 summary

Key learning points

• Bounds use ± half a unit at the stated accuracy.
• Combine bounds carefully for max/min results.
• Choose appropriate accuracy for the context.
• Write error intervals as inequalities.

Worked example 1 — Bounds

$x=4.7$ to 1 d.p. Bounds?

Working

Half of 0.1 is 0.05.

Worked example 2 — Bounds use ± half a unit at the stated accuracy

Use this method from the Number 4 sheet: Bounds use ± half a unit at the stated accuracy.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 3 — Combine bounds carefully for max/min results

Use this method from the Number 4 sheet: Combine bounds carefully for max/min results.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 4 — Choose appropriate accuracy for the context

Use this method from the Number 4 sheet: Choose appropriate accuracy for the context.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 5 — Write error intervals as inequalities

Use this method from the Number 4 sheet: Write error intervals as inequalities.

Working

Each key learning point matches a question type on the printable worksheet.

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.