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Basic geometry and measurement

Course: Basic geometry and measurement>Unit 6

Lesson 2: Volume of rectangular prisms

Volume of a rectangular prism

If you want to know how much stuff you can cram into a box, finding its volume is key. To calculate the volume of a box, you need to know its height, width, and depth. You can find the volume by multiplying these three dimensions together. This formula works regardless of the units you are using (e.g. meters, feet), he method is the same - just make sure your units match up! Created by Sal Khan.

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• why do you multiply the lengths of the sides
• To calculate the area of a quadrilateral, you multiply the length times the width. An example is 5 inches into 3 inches, is 15 inches squared.
• At , He said that it was in meters, but how could it be converted to another measurement type?
• You would just convert the dimensions. In this instance, it is 6m by 7m by 8m.

Then just do what you would regularly do when finding volume - base * height. :)
Best of luck to you!
• help me i don't get this at all an i have a test tomorrow!
• Volume for cubes and rectangular prisms are just
Volume = Length * Width * Height.

All you need to do now is plug the numbers in and use the right units.

If I have a box and it's 8in x 2 in x 9 in I'd do
8*2*9 = 144, but what units do I use?
My units were all in inches and because I did in*in*in my units are in^3.
It's the same for any unit of volume it's all __ ^3.
• Pls upvote for meh thx if you upvote ill quack or u can feed me quackers. (1 fed / 10)
• I upvoted. Now quack for your god.
• I'm confused, will someone explain how to do this plz?
• Volume is easy. For example:
Height: 5 in.
Width: 5 in.
Length: 5 in.
You can multiply length by width or width by length. If you do length by width you will get 25 and the height is 5 so multiply 25x5=125 so the volume is 125 cubic inches. Hope it helps!
• I'm very confused because looking back at my work, I only have two identified sides (technically). I have the width and the base area which is confusing because the base area says that it's measured in units squared, so do I divide the base area by two then multiply the width by the base area by the base area? or no?
• The video tells you the formula is:
Volume = Length (Width) (Height)
If you multiply any 2 of these measurements, you get the area of one side (comparable to your base). Once you multiply the the 3rd measurement, you get the volume

So, in your situation, someone as already multiplied 2 of the dimensions for you since you were given the area of the base. You just need to multiply your 2 numbers to get the volume.

Hope this helps.
• help i don't understand it🥹🥹🥹🥹🥹💚💛
• all you have to do is take all of the numbers and times them all by each other
• help me i don't get this at all
• You need to find the volume by finding its height with and depth and then multiply. Did I answer your question?