China-friendly mirror (cn.improject.org). YouTube may fail on some mainland networks — other resources still work. Global site

Mainland mobile carriers often block or throttle Cloudflare Workers. Reliable phone access needs China CDN (e.g. EdgeOne) and ICP备案 — this mirror is not yet listed on beian.miit.gov.cn.

News

Topic summary · Foundation · CIE Core

Factors, Primes, Powers and Roots summary

Powers and roots sit alongside primes and factors: square numbers, cubes, and estimating roots without a calculator.

Files: foundation-17 Factors, Primes, Powers and Roots.pdf · foundation-17 Factors, Primes, Powers and Roots answers.pdf · free public downloads · diagrams in the PDFs

Key learning points

  • Square numbers and cube numbers — recognise them quickly.
  • Between which integers does 50\sqrt{50} lie?
  • Prime factorisation helps rewrite powers cleanly.

Worked example 1 — Prime factorisation

Write 6060 as a product of primes.

Working

60=22×3×560=2^2\times3\times5

Factor tree.

Worked example 2 — HCF and LCM

HCF and LCM of 1212 and 1818.

Working

HCF=6, LCM=36\mathrm{HCF}=6,\ \mathrm{LCM}=36

From prime factors.

Worked example 3 — Estimate a root

Between which integers is 50\sqrt{50}?

Working

7 and 87\text{ and }8

72=497^2=49, 82=648^2=64.

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.