Author note — to cover

LCM from prime factorisations, taking every prime to its higher index; why the LCM is at most the product and equals it only for coprime numbers; listing multiples as backup. Worded HCF-or-LCM decisions live on choosing-hcf-or-lcm. Both tiers. (N4)

Introduction

—coming soon—

Practice and continue

Practice

Lowest common multiple

Every prime to the higher index, and why the LCM is not always the product.

Next lesson

HCF and LCM from a Venn diagram

The Venn method for two or three numbers, and HCF times LCM as the product.