Using Prime Decomposition to Find HCF and LCM (B) WORKSHEET
Suitable for Year groups: Year 9, Year 10, Year 11
GCSE Tier: Foundation/Higher
Targeting grades: 4-5
Prerequisite knowledge: Finding product of prime numbers of any number
Using Prime Decomposition to Find HCF and LCM (B) WORKSHEET DESCRIPTION
Practice using the prime factor decomposition of pairs of numbers to find the HCF and LCM with this worksheet. In section A, learners will write six numbers from 24 to 308 as products of prime factors before using these to answer four questions on LCM and HCF of these numbers.
Next, in section B, students answer four more questions, including HCF and LCM of three numbers. Pupils are encouraged to use their prime factorisation method from section A.
Learners are required to use these skills to problem solve in section C, with two-worded questions. The worksheet ends with an extension where students consider prime numbers equal to the sum of two square numbers.
