What is Clustering?
Our first student broke numbers down into parts. He split 12 into 10 and 2, which are both easier to multiply than 12. Let's try some problems using this method, which is called clustering. We are clustering the numbers together that are easy for us to multiply.
Goal:
Goal:
25 × 12
We will break 12 into smaller, more manageable numbers, 10 and 2. We don't need to break 25 up any further. We are not doing it in this example because 25 and 10 are easy to multiply and so are 25 and 3.
Did you know that 3 x 42 = 42 x 3? This is called the commutative property. You do not need to remember that term, but you need to remember that you are allowed to switch your numbers when multiplying.