A collection of three worksheets on the following topics:

• Identifying prime numbers. The exercises require to find the factors of given numbers, identify the numbers that are prime and make general conclusions about prime numbers.
• Prime numbers and prime factorisation. The exercises require to decide whether dome given numbers are prime or not and reach some conclusions, find the factors of a number given its prime factoristaion and find the common factors of two numbers given their prime factorisations.
• Finding the prime factorisation of numbers using repeated division by their prime factors and using the prime factorisation of two numbers to obtain their highest common factor.
• Detailed solutions are included.