Introduction

Identify properties of factors and multiples including square and prime numbers, composite numbers, common and prime factors, and common multiples. Use factor pairs to solve problems efficiently.

Teaching points

• Teaching point 1: Factors are positive integers that can be multiplied together to equal a given number.
   
• Teaching point 2: Systematic methods can be used to find all factors of a number; factors come in pairs; all positive integers have an even number of factors apart from square numbers, which have an odd number of factors; numbers with more than two factors are called composite numbers.
   
• Teaching point 3: Prime numbers are positive integers that have exactly two factors.
   
• Teaching point 4: A common factor is a factor that is shared by two or more numbers. A prime factor is a factor that is also a prime number.
   
• Teaching point 5: A multiple of a number is the product of that number and an integer; a common multiple is a multiple that is shared by two or more numbers.
   
• Teaching point 6: The factor pairs of ‘100’ can be used to support efficient calculation.