yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

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?

More Articles

View All
Mughal rule in India | 1450 - Present | World History | Khan Academy
As we’ve talked about in other videos, by the time we get into the 15th century, Timur’s Persia and Central Asia has been fragmented. You have many of Timur’s descendants with their own kingdoms, especially in Central Asia. In 1483, in the Central Asian c…
The Reagans: A Love Story | Killing Reagan
You know, they have been underestimating us all our lives. It was a fairy tale, the two of them against the world. She understood him and knew him and what he needed. He was a very private individual, by all reports very shy, so he had a very good manner …
exposing the dark side of rent control...
What’s up you guys! It’s Graham here. So I’m gonna go on a limb and make this video, and I realize that it’s a bit of a risky topic for me to be discussing: rent control, just given the complexities of the situation. But let’s give it a shot! I’m also gon…
Watch This If You Keep Making Plans but Never Follow Through
I’m a pro procrastinator, and the only time I get motivated is the night before the deadline. When I tell this to people, oftentimes I get recommended to use a planner. Everyone recommends writing things down that I need to do, putting them in an order, b…
What Could Trigger a Shark Attack? | Rogue Shark
Across the Whit Sundays, hundreds of baited cameras are deployed and listening stations fixed as scientists race to understand why these previously safe waters have turned deadly. As the footage comes in, one big clue emerges: the poor visibility. What w…
Partial sums: term value from partial sum | Series | AP Calculus BC | Khan Academy
We’re told that the nth partial sum of the series from N equals one to infinity of a sub n is given by, and so the sum of the first n terms is N squared plus 1 over n plus 1. They want us to figure out what is the actual seventh term. And like always, pau…