Transcript:

So here's an interesting puzzle from Cambridge. So I'm going to set it up for you. It's difficult to read, so I'll explain. The outer square, the big square, has a side length of 12 units. The inner square, the one that is hashed, has a side length of four units. And these two squares are centered, and their sides are parallel to each other. 

OK. Now, the question is: at what point, P, between A and E, does a person have to stand so as to maximize the viewing area? Oh, and the hashed square has walls that are opaque; you can't see through those walls. So, standing at a point P, this person has to maximize the viewing area that is between the outer square and the inner square. 

Now this seems like a tough one, but it is really not so tough. It involves taking areas of triangles and figuring out slopes of lines. So, pause the video now if you want to take a crack at it, because I'm going to reveal the solution now. So here's the solution. If you got it, fantastic! If not, try once more.