Volume of rectangular pyramids using cubes | Grade 7 (TX TEKS) | Khan Academy

less than 1m read

·Nov 10, 2024

We'll be exploring the volumes of rectangular pyramids today with cubes and rectangular prisms. This is a cube; all the sides are the same length. To find the volume of a cube, I can multiply the length by the width by the height. For example, if the length of the cube is five and all sides are the same, then to find the volume I would do 5 * 5 * 5 = 125 cm cubed.

I can break this prism into three rectangular pyramids that are all congruent. So now we have a cube that's actually made out of three rectangular pyramids, and we can see here that all of the rectangular pyramids are congruent. The base of each rectangular pyramid is a square. The square is the same size as one face of our cube, and they all have the same height.

Since all of these rectangular pyramids are congruent, they all have the same volume. To summarize so far, three congruent pyramids can form a cube, and the volume of one of the pyramids will be 1/3 the volume of the entire cube. This is true for all cubes, but what about other rectangular prisms where the sides have different lengths?

High Speed Video of Pistols Underwater - Smarter Every Day 19

Changing equilibria from trade | APⓇ Microeconomics | Khan Academy

View All

TIL: Bees Could Help Save Elephants—By Scaring Them | Today I Learned

[Music] African bees are renowned to be very vicious, and, uh, elephants are terrified because they literally don’t want to have a bee of their trunk stinging them. Elephants tend to rest under very big trees, and if there is a natural beehive, the eleph…

Limitless with Chris Hemsworth | Official Trailer | Disney+

Now I may be in pretty decent shape. Sure, I may look like an immortal Norse God, et cetera. Stop it. But… I know the clock is already ticking. I’m teaming up with the world’s leading Longevity experts. [BREATHES] Taking on six of the toughest tests of my…

Brave New Words - Ethan Mollick & Sal Khan

Hi everyone, it’s here from Khan Academy, and as some of you all know, I have released my second book, “Brave New Words,” about the future of AI in education and work. It’s available wherever you might buy your books. But as part of the research for that …

Introduction to life insurance | Insurance | Financial literacy | Khan Academy

So let’s talk a little bit about what’s probably not your favorite subject. It’s definitely not mine, and that is death. Uh, and uh, it’s not something a lot of us think about. I remember when I was a kid and I used to see these ads on TV for life insuran…

Interpreting graphs of proportional relationships | 7th grade | Khan Academy

[Instructor] We are told the proportional relationship between the number of hours a business operates and its total cost of electricity is shown in the following graph. All right. Which statements about the graph are true? Choose all answers that apply. …

Digital and analog information | Information Technologies | High School Physics | Khan Academy

In this video, we’re going to talk about analog versus digital. Something that’s analog can be any value within a given range, while something digital is represented by a number of discrete or separate levels. To distinguish these two ideas, I like to th…

Volume of rectangular pyramids using cubes | Grade 7 (TX TEKS) | Khan Academy

More Articles