### 1. What does the B in Benoît B. Mandelbrot stand for?

### 2. There are 10 kinds of people in this world.

### 3. Why do mathematicians confuse Halloween and Christmas?

### 4.

### 5. What's purple and commutes?

### 6.

### 7. What's the integral of 1/cabin with respect to cabin?

### 8. What's an anagram of Banach-Tarski?

### 9. An infinite number of mathematicians walk into a bar. The first orders a beer, the second orders half a beer, the third orders a quarter of a beer and so on.

### 10. A museum visitor was admiring a Tyrannosaurus fossil, and asked a nearby museum employee how old it was.

### 11.

### 12. What do you get if you cross an elephant and a banana?

|elephant|*|banana|*sin(theta)

### 13. Why did the chicken cross the Möbius strip?

David Benbennick / en.wikipedia.org

To get to the other–er...

### 14. Let epsilon be less than zero.

michaeljung

### 16. How many mathematicians does it take to screw in a lightbulb?

AaronChoi

0.999999...

### 18. I was dating this topologist once, but we got into an argument over a coffee mug...

4774344sean / Via reddit.com

It torus apart.

### 19. Why aren't jokes in base 8 funny?

m-imagephotography

Because 7 10 11.

### 20. What's the difference between an introverted and extroverted mathematician?

PhoenixNorth

The extrovert looks at your shoes when she talks to you.

### 21. What is non-orientable and lives in the ocean?

Kerstin Meyer

Möbius Dick.

This post has been updated to meet attribution standards.