The array can be shown as 5 groups of 3 showing that 5 x 3 = 15. Or it could be shown as 3 groups of 5 showing that 3 x 5 = 15. This demonstrates that multiplication is commutative. Image caption, ...

Using arrays to find the factors of whole numbers between 10 and 100. Identifying the factors of composite numbers and prime numbers. Using multiplication and division facts to visualise and plan ...