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?

SpaceX-PLOSIONS: Why It Matters - Smarter Every Day 138

How Quantum Computers Break The Internet... Starting Now

View All

Signs You are Moving From Middle Class to Wealthy

You know, it’s easy to tell when someone moves up from middle class, when you know the signs you see. It’s not just about the bank balance. It’s a complete overhaul of your life’s blueprint. Here are ten clear signs you’re moving from middle class to wea…

Why I Love The 'Comfort Zone'

We hear this one all the time: get out of your comfort zone. People tell us that success can be found in the places that we fear and that we should leave familiar territories to explore the unknown. Not getting out of your comfort zone leads to an unsucce…

Lecture 5 - Competition is for Losers (Peter Thiel)

All right, all right, good afternoon. Uh, today’s speaker is Peter Thiel. Peter was the founder of PayPal, Palantir, and Founders Fund, and has invested in, uh, most of the tech companies in Silicon Valley. And he’s going to talk about strategy and compet…

How Far Can We Go? Limits of Humanity (Old Version – Watch the New One)

Is there a border we will never cross? Are there places we will never reach, no matter how hard we try? Turns out there are. Even with science fiction technology, we are trapped in our pocket of the universe. How can that be? And how far can we go? We li…

Bill Ackman Asks Warren Buffett and Charlie Munger How To Analyze Financial Statements

Thank you Bill Ackman from New York New York for the handful. Triple-A rated companies AIG, Fannie Mae, Freddie Mac, and MBIA are under formal investigation for accounting shenanigans and are in the process of restating their financials. Like Charlie said…

History and prehistory | The Origin of Humans and Human Societies | World History | Khan Academy

[Instructor] Anatomically modern human beings have been on this planet for roughly 200,000 years. And even though that’s a small fraction of the amount of time the Earth has been around, which is over 4 billion years, on a human scale, it’s an incredibly …

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

More Articles