It makes sense to think that groups of yellow tiles will make a yellow rectangle.  But that assumes that groups counted by red numbers behave like groups counted by yellow numbers.

But perhaps it doesn't make sense to think of counting groups with red number at all. 

In the next video we will see a way of thinking of multiplying by a red number based on repeated addition. You can then think about about how to represent 5 • 3  by a rectangle.

☐ I'd like to see the next video.

☐ I'd like to review an earlier video.