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## 5th grade (Eureka Math/EngageNY)

### Unit 5: Lesson 1

Topic A: Concepts of volume# Measuring volume with unit cubes

Learn to measure volume of rectangular prisms with cube units. Created by Sal Khan.

## Want to join the conversation?

- If the radius of the base of right circular cylinder is halved. keeping the height same. what is the ratio of the volume of the reduced cylinder to that of the original.(17 votes)
- Since the volume and the radius of the cylinder are both proportionally direct (as one increases, the other increases as well, and the same goes if one decreases), then as we halve the radius, the volume simply halves.(3 votes)

- How many cubes are in 1 layer(11 votes)
- Depends. If it a 6 by 6 by 6, it would be 36 in one layer(8 votes)

- are there any other videos on this?

:)(10 votes)- Yes, there are many other videos on this(5 votes)

- I used to think volume is hard but all you have to do is multiply.(8 votes)
- who likes lemonade(8 votes)
- pink lemonade is better(1 vote)

- khan academy is a really good academy(8 votes)
- to be precise is a nonprofit site(1 vote)

- but if i want to make a bigger volume square i would get bigger results teha change i every dimension(6 votes)
- Hi!

When the dimensions of the shape, such as radius, height, or length change, both surface area and volume also change. However, the volume of the object always changes more than the surface area for the same change in dimensions!

Credits: study.com

Hope this helped! :)(1 vote)

- Can someone help me with volume? its the one were there is fractions involved and it askes about how many cubes there are,i watched the videos, did practices, but i still get the questions wrong,i thought i got the hang of it but when i did the practices i get all of them wrong can someone help me?PLEASE!(2 votes)
- To find the volume of something, you would multiply the objects length, width, and height together, then write the product with the units cubed.(8 votes)

- why is the box bigger than the other box?(4 votes)
- What is the name of the website you used? I would really like to use that too en practice measuring the volume with unit cubes.(4 votes)

## Video transcript

We are asked, what is
the volume of this box? And they tell us that
each cube is a cubic foot. So just as a reminder,
volume is a measure of how much space does
something take up. And it's usually
measured in cubic units. And here we're talking
about cubic feet. And when they say that
each cube is a cubic foot, they're saying that each
of these little boxes, each of these cubes here, is
exactly a 1 foot by 1 foot by 1 foot cube. We're in three
dimensions right now. We're talking about
three dimensions. 3D, you literally
need three dimensions. You need how tall you
are, how wide you are, and how deep you are. And for a cubic foot, each
of those dimensions is one. So each of these
are one cubic foot. The entire shape has one,
two, three, four, five, six cubic feet in it. So the volume of this
entire box is 6 cubic feet. And you see right here
the unit says feet, and it has a
superscript here of 3. This is feet to the third power. You could view this as
feet times feet times feet, or cubic feet. So this is 6 cubic feet. Let's do a few more of these. What is the volume
of this shape? So this one is quite
interesting right over here. You have-- let's see
if we can count these. So you have one, two, three,
four, five, six, seven, eight unit boxes,
or I guess these are cubic inches
for this example. So we have 8 cubic inches. This is a lot of fun, especially
when we get to rotate it. So here, each cube is
a cubic foot again. So we have one, two,
three cubic feet. Let's do one more of these. I like the ones that have
these kind of crazy shapes that we have to rotate to be
able to see all the boxes. So each of these
is a cubic meter, which means that in each
dimension, each of these boxes is a 1 by 1 by 1 meter. But how many boxes are there? Let's see. We have one. We have one. Let me see if I can get a view
where I can look at it better. We have one, two, three,
four, five, six boxes. So the total volume
here is 6 cubic meters.