A child had seven marbles in their pocket, but four fell out. How many marbles are left?
Let’s start by asking ourselves what we need to do to find the answer to this problem. We’re told that there’re seven marbles to begin with. But they’re soon four less than this number because four fall out of the pocket. And we’re asked to find the number of marbles that remain. All of these clues show us that this is a subtraction problem. And we can write this as the number sentence seven take away four equals something.
Let’s sketch the problem to find the answer. So these seven circles represent the seven marbles that the child has in their pocket to start with. But we know that there aren’t seven circles for long. Four circles fall out. So let’s draw a box around four circles just to represent the ones that are no longer in the pocket. So how many marbles are left? Well, our diagram shows that there’re three circles left. Seven take away four equals three.
So the answer to our problem is that after four fall out, there are now three marbles left.