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

Decomposing shapes to find area (grids) | Math | 3rd grade | Khan Academy


2m read
·Nov 11, 2024

Each small square in the diagram has a side length of one centimeter. So, what is the area of the figure? We have this figure down here in blue, and we want to know its area. Area is the total space it covers, and we're also told that each of these little squares has a side length of one centimeter.

That means each of these squares is one square centimeter. We can find the area by seeing how many square centimeters this figure covers. One way would be just to try to draw the little square centimeters and count them. There’s one square centimeter, there’s two, and so on, and keep counting them all the way through.

Or, what we could do is look at this and try to break it into two shapes. We can say down here into two rectangles. Down here, we have one rectangle, and up here, we have a second rectangle. Then we can find the area of each rectangle and add it together to find the total area that the figure covers.

Down here on the bottom, we have two rows of unit squares, and each of those has one, two, three, four, five, six, seven. So, one, two, three, four, five, six, seven. So, there are two rows of seven unit squares or seven square centimeters. The bottom rectangle is made up of 14 square centimeters. It covers 14 square centimeters.

Now, for the top rectangle, let’s see: we have one row, two, three, four, five rows, and each of those rows has one, two square centimeters. So, we have five rows of two square centimeters or 10. This top rectangle here that we have in blue covers 10 square centimeters.

Plus, the bottom rectangle that we outlined in green covers 14 square centimeters. So, in total, the entire figure covers 24 square centimeters. Thus, 24 square centimeters is our area, because area is how much space it covers, and we figured out that it covered 24 square centimeters.

More Articles

View All
2015 AP Biology free response 5
Phototropism in plants is a response in which a plant shoot grows toward a light source. The results of five different experimental treatments from classic investigations of phototropism are shown above. Part A: Give support for the claim that the cells …
Pain in the Crevasse | Continent 7: Antarctica
Okay team, let Mark the shear zone, so come on nice and close behind us. Thank you. The RAS shelf team has traveled about 30 miles, and they’re facing the most dangerous part of their traverse. Oh, we’re just about to enter into the shear zone here. We j…
Homeroom with Sal & Randi Weingarten - Tuesday, August 4
Uh hi everyone, welcome to our homeroom live stream. Sal Khan here from Khan Academy. I’m very excited about the very relevant guest we have today, Randy Weingarten, president of the American Federation of Teachers. Before we jump into that conversation, …
Why more people started flying in private jets
What do you think COVID did for the private aviation industry? Because I’ll be honest, when that whole thing was going on, that was kind of my first introduction to… staring. The charter travel got very crazy. Even though prices were quite crazy at that t…
SPOT THE FAKE !! -------- DONG
Hey, Vsauce. Michael here, coming from Kansas for the 4th of July. Why Kansas? Well, because out here you can do anything. You can even put a firework store next to a gas station. But enough about the real world, let’s talk about DONGs, things you can d…
Inside the Real Black Hawk Down | No Man Left Behind
So the overall mission in Somalia was really a relief operation. We were providing security for the relief organizations who were there trying to distribute food to the starving Somali. Aded was the warlord of the day, so he stepped in and started attacki…