I would read 5x3 as “5 times 3”. That can only be interpreted as 3+3+3+3+3. Can we read 5x3 as “3 times 5”? Can we write “5 times 3” as 5+5+5?

Let’s take an example.

Only 5 different families, send 3 kids from each of them, to a small summer school. How many students are there in the summer school…