Answer:
5 boxes can hold 20 books.
Step-by-step explanation:
In this exercise you have to multiply the number of books that one box can hold plus the number of available boxes.
So the multiplication you have to do is the following:
1 box -------- 4 books
5 boxes --------- X (because we don't know the result)
So you have to multiply 5×4 and you will obtain the reasult of books that can hold "five boxes".
Another way to know the result could be to sum up the total of boxes and the total of books (separately) the result will be the same:
1 box ---- 4 books
1 box ---- 4 books
1 box ---- 4 books
1 box ---- 4 books
1 box ---- 4 books
Total: 5 boxes hold 20 books.