Laughter is the Best Medicine

Base Number Jokes Explained – Numberphile

-There are 10 types of
people in the world. Those who understand binary,
and those who don’t. MATT PARKER: OK, it doesn’t
really work when it’s said. But written down, the
joke kind of holds. Because if I do a 1 and
then a 0, that looks like the number 10. Because you expect it to be
a normal base 10 number. However, if this is in binary,
then this is our units column. That’s our twos column. And so this actually equals
2 in base 10. And so you expect it to
be 10, but it’s not. It’s 2, and that’s the joke. There are actually two
types of people. Those who knew this was binary,
and those who didn’t. -There are 10 types of
people in the world. Those who understand binary,
those who don’t, and those who didn’t expect this joke
to be in base 3. MATT PARKER: OK, good point,
because I guess you– OK, so it depends on the base. So if you’ve got 10, but this
time it’s in base 3, then now you’ve got a units column, and
then a threes column, and then nines, and so on. And so that in normal numbers
would be 3 in base 10. And so the same 1 and 0 in
a different base mean 3. Hence the three categories. -There are 10 types of
people in the world. Those who understand binary,
those who don’t, and– MATT PARKER: Look, you can
generalize it to any base, OK? 10 in base b is going to
equal b in base 10, OK? There’s an infinite set
of these jokes. Cut it out. -There are 10 types of
people in the world. Those who understand
hexadecimal, and F the rest. MATT PARKER: OK, I give it to
you, that one is actually quite funny. Because now in hexadecimal,
which is base 16– 10 in base 16 still does mean
there are 16 types of people. And so there’s the one category
of people who understand hexadecimal,
base 16. But then the remaining
15 in hexadecimal– 15 is just the letter F. And so
when they say F the rest, they’re saying 15
are the rest. Or I guess the joke is the
double meaning, where if you just say F in a sentence, it
means you’re implying– uh, fools. You’re saying they’re very
foolish, all the people who don’t understand hexadecimal. -Why do mathematicians confuse
Halloween and Christmas? Because Oct 31 equals Dec 25. MATT PARKER: OK, so the
joke here is that Oct 31 equals Dec 25. And the surface reading is that
this stands for October, and this stands for December. But it doesn’t. Oct can stand for the eighth
thing, because October is the eighth month in the– it was until Julius Caesar
messed with it. And Dec used to be the 10th
month, blah, blah, blah. So anyway, instead of using
these as months, you can use Oct to mean base 8. So instead of 31 being in our
normal base 10 setup, if we put it into base 8, you
have a units column. You have an eights column. And so you’ve now got one
unit and three 8’s. And three 8’s is 24, plus
a single unit equals 25. And so 31 in base 8 equals 25
in base 10, which is why one equals the other, and
why a mathematician would confuse them. BRADY HARAN: This video was
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myself in the last few weeks. I downloaded a couple of
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fun to be walking through the mountains while listening to
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our videos. [LAUGHTER]

100 thoughts on “Base Number Jokes Explained – Numberphile

  1. I got this one from xkcd. "On a scale from 1 to 10, what is the probability of this question being in binary?" If answer > 2, "what's an n" 'n' being the answer

  2. There are 10 types of people in this world.
    Those who understand binary,
    those who don't,
    and those who weren't expecting a ternary joke!

  3. I know the first joke but i know also the variant what mean:
    there 3 types of people how could count and they how couldn`t…
    or the next one is also quit funny:
    Son: iΒ΄m cold
    Father: go in the coner there are 90 degres

  4. sometimes I wonder why I bothered learning base 2. do I ever use it? no. if I told one of those jokes I would look like I'm trying to be smart, which I'm not, because I wasted time learning binary.

  5. it looks more computer guys jokes than mathematician one but I loves thems (because I understand it !! πŸ™‚ )

  6. math joke:
    where you said how many youtube vids are there youΒ put your head in a parker square.
    classic parker square

  7. Ask a programmer or apparently a mathematician what 1100 = in binary and he will tell you 12. Ask an electronic tech what 1100 = in binary and he will tell you 3. Why? Because a programmer or mathematician reads numbers from high to low – left to right the same way numbers are written in most languages; ie, $5,280.00. Most electronic techs are used to viewing binary counters – a single LED for each bit – increment from left to right, low bit to high bit. A programmer will write out the bits like this; 128 64 32 16 8 4 2 1 while an electronic tech will put them in a schematic as 1 2 4 8 16 32 64 128. The pin-outs on the first binary counter ICs were more conducive to this "backwards" displaying. The 6800 and 6500 series microprocessor actually work with numbers from low bit to high bit, but then flip it around so mathematicians can understand it.

  8. β€œBecause October is the eighth… was the eighth month until Julius messed it all up”
    Back off Julius, what’d he ever do to you?

  9. 0:43 If those are three groups that everyone must fall in to one of, wouldn't that mean that everyone who didn't expect this joke to be in base three neither understand binary, nor don't understand binary, and that everyone who either understands, or doesn't understand binary was expecting this joke to be in base three?

  10. There are 10 types of people in the world
    Those who understand binary
    Those who don't
    Those who thought they were smart solving this joke with base 3
    Those who thought they were smart solving this joke with base 4
    Those who thought they were smart solving this joke with base 5
    Those who thought they were smart solving this joke with base 6

    And those who didn't think about infinity

  11. There are ten types of people in the world
    Those who understand binary, and those who don't

    And those who weren't expecting a ternary joke

  12. There are 10 types of people in the world; those who understand binary, those who don’t understand binary, those who kinda understand binary, those who expected this joke to be in base 5 and those who didn’t expect this joke to be in base 5.

  13. Ternary? Isn't that supposed to be Trinary?

    Hmm, maybe not. Spellcheck likes Ternary more. I've been saying it wrong my whole life!

  14. Alien: There are 10 rocks.
    Human: Oh, you must be using base 12.
    Alien: No, I'm using base 10.

    The joke is that if you are using base 12, for example, you would still represent 12 as 10.

  15. October was already the 10th month way before Julius Caesar's time. July was called Quintilis and August was Sextilis. The strange numbering is from hundreds of years before the Roman Empire, presumably from a time when the year began in March. Those two summer months, Quintilis and Sextilis, were simply renamed in the Caesars' honor (hence why they're the only adjacent months with 31 days, for equal honor). The Julian calendar reform was much less drastic, as he was already working with a 12-month year.

  16. ”F is for foolish, you’re saying they’re very foolish that’s the joke.” Yeah, foolish. Definitely.

  17. There are 10 types of people in the world, those who know binary, those who do not, and aNyone besides that!

  18. Now I understand base numbers… THANKS NUMBERPHILE! I more than likely will need this in high school math here soon…

  19. October is simultaneously the eighth (in name) and tenth (in position) months and December is the tenth and twelfth month…
    The other hidden meaning of the "non-joke" is that non-inclusive of October 31, there are 55 days to the 25th of December and that SANTA=55

  20. Three positions for OCTAL with HEX (think about it) would be FFF which is the sixth letter of the alphabet…Could not be more obvious as to the connotations of pointing that out.

  21. Octal written as 010 is still equal to two…Octal condensed as 000001000 is eight decimal so that is incorrect in the video.

  22. Every system has a base 10.

    2 in bin = 10. (Binary system has base 2. But 2 is 10 in binary.)
    8 in oct = 10
    16 in hex = 10
    10 in dec = 10

  23. They are implying that, uhh, the rest are fools. Smiles awkwardly


  24. "because octoctober is the 8th month in the-, it was before Julius messed with it" – he says it like he knows the guy!

  25. at 2:42 : "October was eighth month until Julius Caesar messed with it", Actually, one of the Caesar's predecessors, King Numa Pompilius messed with it by including two months January & February before the first month of Calendar March (then known as Martius) to include 51 days beyond 31 December which were not in a 10 month calendar that existed before him.

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