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## 5th grade (Eureka Math/EngageNY)

### Unit 2: Lesson 4

Topic D: Measurement word problems with whole number and decimal multiplication- Converting units: minutes to hours
- Convert units of time
- Converting units: metric distance
- Converting units: centimeters to meters
- Convert units (metrics)
- Metric units of volume review (L and mL)
- Metric units of mass review (g and kg)
- Metric units of length review (mm, cm, m, & km)
- Converting units of time review (seconds, minutes, & hours)
- Converting units: US volume
- Same length in different units
- Convert units (US customary)
- Convert units word problems (metrics)
- US Customary units of volume review (c, pt, qt, & gal)
- US Customary units of weight review (oz & lb)
- US Customary units of length review (in, ft, yd, & mi)
- Time word problem: Susan's break
- Measurement word problem: tea party
- Convert units multi-step word problems (metric)
- Convert units word problems (US customary)
- Measurement word problem: blood drive
- Measurement word problem: distance home
- Measurement word problem: elevator
- Measurement word problem: running laps

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# Converting units: US volume

CCSS.Math:

Learn to convert 3 1/2 gallons to cups. Created by Sal Khan and Monterey Institute for Technology and Education.

## Want to join the conversation?

- What is an easier way to remember how to convert between measurements?(25 votes)
- You should be able to remember by the kingdom of G. Draw a big G (for gallons) inside draw four Q( for quarts) inside of the Q draw two P(for pints) and inside of that draw 2 C (for cups). The story goes something like this, there once was a kingdom G that had 4 queens. Each queen had two princesses. Each princess had two cats . The end.(47 votes)

- Why does there have to be the U.S customary units? Why can't we all just use the metric? It's a lot easier!(19 votes)
- Probably because US units is important because they are used a lot in the US, and people need to know how to use them effectively, but I agree with you fully(2 votes)

- 1 ounce per gallon, how much of the ounce for 1 cup?(5 votes)
- For every ounce per gallon, there is .0625 ounces per cup.(2 votes)

- To clarify product is between point 1125-point 225 it is difficult to see dec point(5 votes)
- This isn't really related to math (well I guess it is) but isn't pints pronounced like tints but the t is a p?(3 votes)
- Though pint
*appears as if*it would be pronounced like*tint or mint*, instead it's an odd one out of the usual…

The letter**i**in pint and pints,

is asound,**long i**

just like the**i**in**pine**.

As in pine tree, 🌲

also like shine, or devine.

Say the word:**pine**,

then**include a quick T**sound at the end.

(ㆁωㆁ) Hope this helps.(4 votes)

- How do you remember like how many oz go into a lb and all that stuff?(2 votes)
- 16 oz in a lb

8 oz in a cup

2 cups in a pint

4 cups in a quart

16 cups in a gallon

2 pints in a quart

8 pints in a gallon

4 quarts in a gallon(6 votes)

- Any easy way to remember this? A saying or something?(2 votes)
- Could you also have made the 3 1/2 into 3.5 gallons and multiplied it by 16? It comes out as the same answer.(3 votes)
- Yes that method is correct, because there are 16 cups in a gallon (4 cups in a quart, and 4 quarts in a gallon).(3 votes)

- I do not get the model in the lesson(4 votes)
- The entire cube is a gallon, the quarters of it are quarts, and the halves of each quart are pints, and the halves of each pint are cups, making one cup equal to 1/16 of a gallon.(1 vote)

- I thought that there are 4 pints per quart and 4 cups per pint.(2 votes)
- Nope, it’s a bit confusing, but there are 2 pints per quart and 2 cups per pint.(4 votes)

## Video transcript

How many cups are in
3 and 1/2 gallons? So before even addressing this
question, let's just think about how large a cup is. Actually, I'll give you a little
bit of overview of how many cups there are in a pint,
how many pints in a quart, and how many quarts in a gallon. Let me just draw a cube here,
and let's imagine that this is a gallon. The most common time we see
a gallon is when you see a gallon of milk. So let's say that that whole
thing is a gallon. You can imagine if it had a
handle, it would be kind of a big gallon of milk. Now, there are 4 quarts
per gallon. Let me write this over here. There are 4 quarts per gallon. So if I were to draw the quarts
here, I could divide this gallon into 4 quarts, and
then each of these sections would be a quart. So you would have 4 quarts. So this right here that I've
just drawn in blue would be exactly 1 quart. And obviously, there's 4 of them
in this entire gallon. Now, you can divide the
quarts into pints. You have 2 pints per quart. So this quart that I drew here,
I can divide it into 2, like that, and this little
section that I'm highlighting in magenta is a pint. That is a pint right
over there. And then finally, there
are 2 cups per pint. So this pint right here, I can
divide it into 2, and each of these will be a cup. So this section right
here will be a cup. Now, we can go straight and
figure out exactly how many cups there are per gallon. Actually, that might be
an interesting way to think about it. If you have 4 quarts-- let's
multiply it right here. So you have 4 quarts per gallon times 2 pints per quart. What does this give you? This gives you 4 times
2 is equal to 8. And then the quarts cancel
out, and you have 8 pints per gallon. And that makes complete sense
because we had 4 quarts in this gallon, and then
each of those quarts have 2 pints in them. So 4 times 2. So 8 pints per gallon. And then we can multiply that
times 2 cups per pint. So I could just copy and
paste this right here. Actually, I should've
cut and paste. Let me select it again. I want to do that so I get
that real estate back. So edit, cut, edit, paste. There you go. So now you multiply this
times 2 cups per pint. And the reason why this will
work is because you have pints in the numerator. It cancels out with the pints
in the denominator. And you will be left with-- I'll
go back to the yellow-- 8 times 2 is 16. In the numerator, we have
cups per gallon. Now, we just figured how many
cups there are per gallon. That makes sense. This section right here is
exactly 1/16 of this entire cube, this entire gallon. But we haven't even answered
our question. We want to figure out how
many cups there are in 3 and 1/2 gallons. So let's write it over here. So we're concerned with
3 and 1/2 gallons. I don't like working
with mixed numbers. I like to turn them into
improper fractions. 3 and 1/2 is the same thing as
2 times 3 is 6, plus 1 is 7. This is the same thing as 7/2. If you divided 7 by 2, you would
get 3 with a remainder of 1, or this would be
3 and 1/2, so this is the exact same thing. So we want to know how many
cups are in 7/2 gallons. So what we want to do is end up
with cups, and we want the gallons to cancel out. So we have gallons in the
numerator right here. It's definitely not in
the denominator. And so we want to divide
by gallons. And then we're going to
have a numerator. We have cups in the numerator. And how many cups are
there per gallon? Well, we just figured
that out. There are 16 cups per gallon. When you multiply these two
quantities, the gallons will cancel out, and you'll just be
left with cups, and that's what we wanted. So it's going to be
7/2 times 16. So this is going to be
7 times 16/2 cups. You could divide 16
by 2 to get 8. 2 divided by 2 is 1. So it just becomes 7 times 8
divided by 1, or just 7 times 8, which is 56. So this is equal to 56 cups. And this should make sense. This should be a much larger
number because cups are a much smaller unit. So if you have 3 and 1/2
gallons, you will have many, many, many more cups in that
3 and 1/2 gallons, so this makes sense.