I prefer snappier versions of the first half, like:
An infinite number of mathematicians walk into a bar. The first says, "Give me a beer." The second says, "I'll have a half a beer." The third says, "A quarter of a beer, please." The bartender pours two beers and says, "Come on, people. Know your limits."
An infinite number of mathematicians walk into a bar. The first says, "Give me a beer." The second says, "I'll have a half a beer." The third says, "A quarter of a beer, please." The bartender pours two beers and says, "Come on, people. Know your limits."
Copy-pasted from https://owlcation.com/stem/Worst-Math-Jokes-and-Math-Puns, but there are many similar versions.