why would the water move up that amount if there is a hole in the center of the ring? Wouldn't that hole fill up and change the amount of space the water takes up?

We are interested in the volume of the "gold". The hole in the ring fills up with water but the gold doesn't. So the water displaced by the ring is the volume of the gold

At 0:10, How come the inches in the water increase?

the ring's volume is 1.5, so it displaces the water so it stays even, Because atoms cant go inside of each other...

how do you find the area of a square.

Width squared. Think of it like a line 3 inches long 3 times, as an example.

how to find area of box

A box is a 3D object, so you can either find the volume or the surface area, but there is no such thing as area of a 3D object.

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7th grade

Course: 7th grade > Unit 6

Lesson 9: Volume and surface area word problems

Volume word problem: gold ring

Name: Volume word problem: gold ring
Uploaded: 2013-10-27T05:44:06Z
Description: See if you can find the incremental volume of a ring in cubic inches. You'll need to put to use your knowledge of how to measure volume.

Google Classroom

See if you can find the incremental volume of a ring in cubic inches. You'll need to put to use your knowledge of how to measure volume. Created by Sal Khan.

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Taylor Dunfee
Posted 9 years ago. Direct link to Taylor Dunfee's post “why would the water move ...”
why would the water move up that amount if there is a hole in the center of the ring? Wouldn't that hole fill up and change the amount of space the water takes up?
Button navigates to signup pageComment on Taylor Dunfee's post “why would the water move ...”
(7 votes)
Answer
- Agent Smith
  Posted 9 years ago. Direct link to Agent Smith's post “We are interested in the ...”
  We are interested in the volume of the "gold". The hole in the ring fills up with water but the gold doesn't. So the water displaced by the ring is the volume of the gold
  Comment on Agent Smith's post “We are interested in the ...”
  (14 votes)
Shreyas Girish Jamadagni
Posted 6 years ago. Direct link to Shreyas Girish Jamadagni's post “Wouldn't the volume of th...”
Wouldn't the volume of the ring be just 0.25 cubic inches? as the ring does not have a length of 3 inches and width of 2 inches?
Button navigates to signup pageComment on Shreyas Girish Jamadagni's post “Wouldn't the volume of th...”
(6 votes)
Answer
- Brad
  Posted 25 days ago. Direct link to Brad's post “The water level rises by ...”
  The water level rises by 0.25 inches.
  If you get 0.25 inches (height added) and multiply it by length and width (2 and 3) You get the total amount of water dispaced, which is the area of the ring. If you multiply your length times your width,(3x2) you get 6. 6 times 0.25 extra height =1.5 or *6 x 0.25 = 1.5
  ---Hopefully this makes it a little bit easier---
  Button navigates to signup page
  (1 vote)
Robbie Russo
Posted 8 years ago. Direct link to Robbie Russo's post “At 0:10, How come the inc...”
At
0:10
, How come the inches in the water increase?
Button navigates to signup pageComment on Robbie Russo's post “At 0:10, How come the inc...”
(4 votes)
Answer
- Troyal Diefenderfer|Firekit|BeamNG.Drive Mod tester|
  Posted 8 years ago. Direct link to Troyal Diefenderfer|Firekit|BeamNG.Drive Mod tester|'s post “the ring's volume is 1.5,...”
  the ring's volume is 1.5, so it displaces the water so it stays even, Because atoms cant go inside of each other...
  Comment on Troyal Diefenderfer|Firekit|BeamNG.Drive Mod tester|'s post “the ring's volume is 1.5,...”
  (3 votes)
nikki
Posted 6 years ago. Direct link to nikki's post “I have 2 questions. How c...”
I have 2 questions. How could volume be in cubic inches? Why do you need to leave out the '4' in the height when solving for the mass of the ring?
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(4 votes)
Answer
Xtartt
Posted 8 years ago. Direct link to Xtartt's post “should you always divide ...”
should you always divide the biggest number by the smallest number in whatever volume problem you are doing? Also, what is the formula for volume problems? Because it wasn't explained in the video, I ended up getting the problem wrong.
Button navigates to signup pageComment on Xtartt's post “should you always divide ...”
(3 votes)
Answer
Hannah Miller
Posted 3 years ago. Direct link to Hannah Miller's post “So, basically, you can fi...”
So, basically, you can find the volume by finding the biggest object, then subtract the space that isn't the smaller object inside, right?
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(3 votes)
Answer
ConnorK
Posted a year ago. Direct link to ConnorK's post “how do you find the area ...”
how do you find the area of a square.
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(2 votes)
Answer
- Kimi
  Posted a year ago. Direct link to Kimi's post “Width squared. Think of i...”
  Width squared.
  Think of it like a line 3 inches long 3 times, as an example.
  Button navigates to signup page
  (2 votes)
Jonathan
Posted 6 years ago. Direct link to Jonathan's post “so you can know the ring'...”
so you can know the ring's volume just like khan said at
1:38
?
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(2 votes)
Answer
- Induja (Pihu) Shukla
  Posted 3 months ago. Direct link to Induja (Pihu) Shukla's post “Yea dude use the method h...”
  Yea dude use the method he taught you in the video.
  Comment on Induja (Pihu) Shukla's post “Yea dude use the method h...”
  (1 vote)
27jdesmarais
Posted a year ago. Direct link to 27jdesmarais's post “how to find area of box”
how to find area of box
Button navigates to signup pageButton navigates to signup page
(1 vote)
Answer
- David Severin
  Posted a year ago. Direct link to David Severin's post “A box is a 3D object, so ...”
  A box is a 3D object, so you can either find the volume or the surface area, but there is no such thing as area of a 3D object.
  Comment on David Severin's post “A box is a 3D object, so ...”
  (3 votes)
Oof It's Crazy Kellie
Posted 4 years ago. Direct link to Oof It's Crazy Kellie's post “Couldn't he just, like, f...”
Couldn't he just, like, find the volume of it by figuring out the volume of a cylinder?

It seems as if he could measure the height of the ring and the radius. Find the volume of that, then find the volume of the HOLLOW part the exact same way but subtracting the 'crust' from the diameter, then subtract? That seems more reasonable to me. Anyone know what I mean??
Button navigates to signup pageComment on Oof It's Crazy Kellie's post “Couldn't he just, like, f...”
(2 votes)
Answer

Video transcript

Jamie wants to know the volume of his gold ring in cubic inches. He gets a rectangular glass with base 3 inches by 2 inches. So you see that here, the base is 3 inches by 2 inches. And he fills the glass 4 inches high with water. So you see that over here, 4 inches high with water. Jamie drops his gold ring in the glass and measures the new height of the water to be 4.25 inches. So this is after the gold ring is dropped. What is the volume of Jamie's ring in cubic inches? Well when you start with this water right over here and you add his ring, whatever that volume is of his ring is going to displace an equal volume of water and push it up. And so the incremental volume that you now have is essentially going to be the volume of his ring. Well what is the incremental volume here? Well it's going to be the volume. If you think about going from this before volume to the after volume, the difference is the base stays the same. It's 3 inches by 2 inches, the difference is-- to make it a little bit neater-- the base is the same. The difference is the height. The height now is 4.25 inches after dropping in the ring So the water went up by 0.25 inches. Let me write that, 0.25 inches is what the water went up by. So we could just think about, what is this incremental volume going to be? So this incremental volume right over here, that I'm shading in with purple. Well to figure that out we just have to measure. We just have to multiply the length times the width times the height times 0.25. So it's just going to be 3 times 2 times 0.25. 3 times 2 is 6, times 0.25, and you could do that either on paper or you might be able do that in your head. 4 times 0.25 is going to be 1, and you have 2 more times 0.25, that's going to be 0.5. So this is going to be 1.50. And we multiply it inches times inches times inches. So this is going to be in terms of cubic inches. 1.5 cubic inches is the volume of Jamie's ring, which is actually a pretty sizable volume for a gold ring. Maybe he has a very big finger or he just likes to spend, or I guess is his, whoever bought him the ring likes to spend a lot on gold.