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Current time:0:00Total duration:4:26

- [Instructor] We are told that Billy has 1/4 of
a pound of trail mix. He wants to share it equally between himself and his brother. How much trail mix would they each get? So pause this video and
try to figure that out. All right, now let's work
through this together. So Billy starts with 1/4
of a pound of trail mix. So how can we represent 1/4? Well, if this is a whole pound, let's just imagine this
rectangle is a whole pound, I could divide it into
four equal sections. So let's see, this would be
roughly two equal sections, and then if I were to divide
each of those into two, now I have four equal sections. So Billy is starting with 1/4 of a pound. Draw a little bit, try to make
it a little bit more equal. Billy is starting with 1/4 of a pound, so let's say that is that 1/4 of a pound that he starts with. He's starting with 1/4 of a pound, and he wants to share it equally between himself and his brother. So he wants to share it equally between two people right over here. So what we wanna do is essentially say, let's start with our
total amount of trail mix, and then we're going to divide
it into two equal shares. So when they ask us how much
trail mix would they each get, we're really trying to figure out what is this 1/4 divided by two? So what would that be? Well, what if we were to take all of these four equal sections
and divide them into two? So I'll divide that one into two. I will divide this one into two. I will divide this one into two, and then I would divide this one into two. And now what are each of these sections? Well, each of these are now 1/8. That's a 1/8 right over there, the whole is divided into
eight equal sections. And so you can see, that
when you start with that 1/4, and you divide it into two equal sections, so one section and two equal
sections right over there, each of these is equal to 1/8. So 1/4 divided by two is equal to 1/8. Let's do another example. So we are told Matt is
filling containers of rice. Each container holds 1/4
of a kilogram of rice. And then they tell us if Matt
has three kilograms of rice, how many containers can he fill? So like always, pause this video, and see if you can figure that out. All right, so let's think
about what's going on. We're starting with a total
amount, three kilograms of rice, and we're trying to divide
it into equal sections. In this case we're trying to
divide it into equal sections of 1/4 of a kilogram. So we are trying to figure out what three divided by 1/4
is going to be equal to. Now to imagine that, let's
imagine three wholes, this would be three whole kilograms. So that is one whole, this is two wholes, trying to make them all the
same, but it's hand-drawn, so it's not as exact as I would like. So that's three whole kilograms here. And he wants to divide
it into sections of 1/4. So if you divide it into fourths, how many fourths are you going to have? Well, let's do that. So let's see, if we were
to divide it into halves, it would look like this. If you divide these
three wholes into halves. But then if you want to
divide it into fourths, it would look like this, I'm trying to get it as
close to equal sections. They should be exactly equal sections. So I am almost there. So there you have it. So I've just taken three wholes and I've divided it into fourths. So how many fourths are there? Well, there are one, two,
three, four, five, six, seven, eight, nine, 10, 11, 12 fourths. So three divided by 1/4 is equal to 12. And I encourage you to really think about why this is the case, that if we take a whole number like three and you divide it by 1/4, we're getting a value larger than three. And we're getting a value
that is four times three. Think about why that is the case.