Part of being on Facebook is tolerating the “memes” that every single one of your friends feels compelled to post. It happens in waves: One group does the original posting, then there’s a week of silence, and then suddenly the same exact joke — or pithy statement, or picture of a puppy — comes back with a vengeance as the next group of friends jumps belatedly on board.

We’re on round three, at least, of the puzzle shown below, which I think may have been posted by every single radio station in the country, and always with the same weird caption: “We count 24 squares in the image below. How many do you see?” What then follows in the comments is a bewildering debate as people claim they see any number of squares from 20 to 100.

Let’s clear this up, shall we? There are 40 squares. Forty. Let’s count ’em together!

We’ll start by ignoring the two squares in the center. Just focus on the largest square for a moment. This square is 4×4. That is to say there is 1 4×4 square.

Within that 4×4 square are 4 3×3 squares:

Also within that 4×4 square are 9 2×2 squares.

And finally, there are also 16 1×1 squares.

16 + 9 + 4 + 1 = 30

Now consider the two squares we previously decided to ignore. Each one encompasses five squares: Itself, and the four smaller squares within it. That’s ten more squares, bringing us to a grand total of 40.

There, that takes care of that! Glad to be of service.

By the way, how many stars are there in the image below?

Via Jeffrey Harris: What is the only chemical element whose name contains no symbols for chemical elements?

I’ll go so far as to hint that the answer is a very commonly known element, and not, say, Ununpentium.

Update: And look at that: Jeffrey has also posted a Marching Bands to his Web site. “Turning 27” refers both his new age (happy birthday!) and the fact that there are exactly 27 words turning within the bands.