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## Arithmetic

### Course: Arithmetic > Unit 10

Lesson 4: Multiplying fractions and whole numbers word problems# Multiplying fractions word problem: milk

Sal solves a multiplication fraction word problem about milk. Created by Sal Khan.

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- how is 6/1 = to 6(0 votes)
- because 1/1 is equal to 1 whole so 6/1 is equal to 6(8 votes)

- what does energy points mean(0 votes)
- Energy Points are points you earn for working on assignments and/or goals in Khan Academy. Hope this helps! :)(10 votes)

- did khan academy ever look like what it looks like in this video?(4 votes)
- Is 6/1=6 because it’s a improper fraction?(3 votes)
- I got confused about something about halfway through. How exactly does 20/5 equal 4??(0 votes)
- 20 ÷ 5 = 4. If the fraction is improper check if you can divided the numerator by the denominator.

Happy to help!(4 votes)

- do you now Wikipidea.(2 votes)
- what does energy points mean(0 votes)
- An energy point is something you earn when you complete a lesson, test, or watch a video. The more energy points you have, the better avatars you get. For example, my avatar is a level four Duskpin. You need to have a total of 100,000 energy points. You don't need to buy the avatars because Khan Academy just unlocks the available avatars immediately. You can also earn badges by accumulating a specific amount of energy points. That is basically my summary of energy points, and if I put anything that is incorrect, please tell me!(6 votes)

- show me how to solve. Lana was trying to collect 3 pounds of cans . If she collects one-fourth of a pound each day, how many days will it take to collect 3 pounds,(1 vote)
- When I answer the questions I answer them correctly but what I don't understand is why they don't explain the strategies so we fully understand how this strategy is helping me find the answer. It is hard for me to answer the questions they give us when I don't understand them even if I get them right it seems confusing still. Can you help me understand it better.(1 vote)
- I still don't get it

What do you meen(1 vote)

## Video transcript

If there are 6 people
in your family, and each person drinks 4/5 of
a gallon of milk each month, between what two whole numbers
is the number of gallons of milk your family
will drink each month? So let's think about
this a little bit. So I've got my milk gallon
here for inspiration. So there's 6 people
in my family, or in your family, whoever's
family we're talking about. And each of them drink
4/5 of a gallon per month. So we're going to go 6
times 4/5, or 4/5 times 6. Now, what is this
going to be equal to? Well, there are several ways
we could think about this. One, we can express
6 as a fraction. We could say that this is the
same thing as 6/1 times 4/5. And you multiply the numerators. You multiply the denominators. 6 times 4 is 24. And 1 times 5 is 5. So 24/5 gallons are going
to be drunk every month. And this is the same
thing-- let's see, 5 goes into 20 evenly
and has a remainder of 4. So we could write this
as 20/5 plus 4/5 5-- let me move over a little
bit so I don't run out of space, which
is the same thing. This is 4. So this is 4 and 4/5. So that's one way
to think about it. The other way, you could
think of this as 4/5 times 6, which is the same thing
as 4/5 plus 4/5 plus 4/5-- I think you get the idea--
plus 4/5 plus 4/5 plus 4/5. We took literally six 4/5's
and added them together. And what's this
going to be equal to? Well, this is going to
be 4 plus 4 plus 4 plus 4 plus 4 plus 4 over 5. This is how many 1/5's we have. Well, this is 6
times 4, or you could say 4 times 6, over 5,
which is equal to 24 over 5, which we've already
figured out is 4 and 4/5. So either way,
we're going to drink 4 and 4/5 gallons per month. Now let's try to answer
the actual question. Between what two whole numbers? Well, between 4 and
5 gallons a month. 4 and 4/5 is right
in between 4 and 5. We got it right.