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## Equivalent fractions

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# Equivalent fraction word problem example

## Video transcript

You are filling up
trays to make ice cubes. You notice that each tray holds
the exact same amount of water but has a different number
of ice cubes that it makes. The blue tray makes 8
equally sized ice cubes. The pink tray makes 16
equally sized ice cubes. So let me draw the
blue tray here. The blue tray, I'll
draw it like this. That is not blue. Let me draw it in blue. So the blue tray makes 8. So this is the blue
tray right over here. And let me draw it and
divide it into 8 sections to represent the 8
equally sized ice cubes. And I'll try to do it. So, let's see. That's about in
half, and then I'm going to put each of those
in half, and then each of those in half. So there we go. This is pretty close to
8 equally sized cubes, except for this one there. Let me actually make it
a little bit cleaner. So there's the half,
half, half, half, half. All right, so this is
looking a little bit better, so 8 equally sized ice cubes. This is the blue tray. Now, the pink tray takes
the same amount of water, so I'm going to make it
the exact same length. So the pink tray is
the exact same length, but it has 16 equally
sized ice cubes. So what I'm going
to do is I'm going to make these same
sections here, but then I'm going to cut
these sections in two. So that's 8, and to 16, I
got to divide these into two. So almost done. This is the hard part. That last one wasn't that neat. Almost done. All right. There we go. Set up the problem. Now, you put 3 ice cubes from
the blue tray into your drink. So, let's do that. So, 1, 2, 3 ice cubes from
the blue tray into your drink. How many ice cubes
from the pink tray would you need to equal the
same exact amount of ice? So there's a bunch
of ways to do it. We can think about
it with numbers, or we can think
about it visually. Let's first think
about it with numbers. So how much of this
tray have I pulled out? Well, I have 8 equally sized
cubes and I took 3 of them out, so this literally
represents 3/8. So the question
is 3 over 8, if I take 3 out of 8 equally
sized cubes, that's the same quantity
as taking what? I want to do that in white. That's the same
quantity as taking how many cubes out of 16, out
of 16 equally sized cubes? Well, let's look at
it over here visually. So if we want the exact
same amount of ice, so we're gonna have
1, 2, 3, 4, 5, 6. We have 6/16, so this
is equal to 6/16. Now, does that
make actual sense? Well, sure. To go from 3/8 to 6/16, you
multiply the numerator by 2, and you multiply the
denominator by 2. Now, does that
actually make sense? Well, sure it does. Because for the
pink ice tray, you have 2 ice cubes for every 1
that you have in the blue ice tray. So the blue ice tray, you
have 8 equally sized cubes. Well, for each of
those, you're going to have 2 in the pink
ice tray, so you multiply by 2 to have 16
equally sized cubes. And out of the blue tray,
if you take 3, well, that equivalent amount
for each of those cubes, you would get 2 from
the pink ice tray. So you're multiplying
by 2 right over there. So the answer to the
question, how many ice cubes from the
pink tray would you need to equal the
same amount of ice? Well, that is you
would need 6 cubes.