Step 4 Objective

Factorise numbers to 100 into prime factors.

Examples of what pupils should know and be able to do

Write 24 as a product of primes.

Probing questions

How do you go about finding the prime factors of a given number?

What are the prime factors of 125? 81? 343? What do you notice?

Can you think of a number that has one repeated prime factor? Or all different prime factors?

What if pupils find this a barrier?

Show pupils how to use factor trees to find the prime factor decomposition of a number.

(FTM(S)Y789 p. 53) - Acrobat pdf document (34Kb)