 So, an important idea in dealing with fractions is known as the concept of equivalent fractions. And what we have is we have two different divisions representing the same amount. And so, for example, I might have the division three-fifths and I might have the fraction nine-fifteenths. And what I'd like to do is, if possible, to show that these two are equivalent. So, I might begin by trying to represent three-fifths. And so, this is I'm going to take a whole divided into five equal parts and then shade three of those parts. So, there's my whole three-fifths, three of those parts. Now, what if I want to represent nine-fifteenths? So, what I'm going to do here is I'm going to take the whole and rather than draw fifteen vertical parts, what I'm going to do is I'm going to split this up a little bit. And I'm going to take advantage of the fact that I can divide something into fifteen by first dividing it into five parts and then dividing it into three parts. So, there's my division into fives, there's my division into threes. And so, now I have fifteen equal parts and I want to shade nine of those parts. And so, there's my nine-fifteenths. So, here's three-fifths, here's nine-fifteenths. And the question is, I want to show that these two are equivalent. Well, there it is. I can look at the picture and see that three-fifths, nine-fifteenths, represent exactly the same amount.