Skill: Use the commutative property of multiplication

When you multiply two whole numbers, you can switch their order without changing the answer.

For example, find $3 \times 4$.

1. Think of $3 \times 4$ as 3 rows of 4:

$$\begin{array}{cccc} \bullet & \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet & \bullet \end{array}$$

2. Count the objects. There are $12$, so:

$$3 \times 4 = 12$$

3. Turn the array. Now it has 4 rows of 3:

$$\begin{array}{ccc} \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet \end{array}$$

4. The number of objects is still $12$, so:

$$4 \times 3 = 12$$

Therefore, switching the factors gives the same product:

$$3 \times 4 = 4 \times 3 = 12$$

This can help you remember multiplication facts: if you know one fact, you also know the fact with the factors reversed.