Chloe has seven books. If each book is four inches thick and she stacks the books on top of one another, how high is the stack?
Here’s Chloe’s shelf. And here are her seven books stacked on top of each other. We know that each book is four inches thick. We could add four inches plus four inches over and over again, seven times. A better option to that repeated addition is multiplication.
Multiplication represents repeated addition. In this case, multiplication would look like four inches per book times seven books. Four times seven equals 28. And then we see that if each book was four inches tall, the stack of seven books is 28 inches tall.