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, ...

understand that the area of a rectangle is the result of a multiplication partition (break apart) a number using your understanding of place value recall times-tables up to 9 x 9 and multiply by ...