Pi is exactly 3!
Three, no more, no less. Three is the number of pi. Four should not be pi, neither two. Five is right out.
1, 2, 5!
3 sir!
Oh yes! 3!
so 6?
Tau
Now I want to see the original letter. For some reason this reminds me of David Thorne (27bslash6)
This isn’t really a meme
This beats the approximations used in ancient Sumer (3.1065) and China (3). Try contacting their respective records bodies.
Gotta say, using 3 just feels like giving up due to laziness, even in 1200BC.
Also it’s interesting how the Chinese entries basically stop between 1400 and 1949, whereas European names are far more present during this era. Some Japanese ones, too. I wonder how comprehensive this page is.
AFAIK the Chinese knew that the value between that of the encompassing shape that meets the circle at tangeants to the inscribed shape whose edges meet the same equidistant points gives us the approximation of pi. So did archimedes, and maybe even the babylonians.
So while a triangle yields about 3 and satisfies the theorem, you could also theoretically draw a 96 gon and 192 gon like Liu Hui for an accuracy of 9x10^5.
Personally I just memorize 22/7 or use the Leibniz infinite series if I have to.
Sometimes zero decimals is enough precision even in 2025…
…but also because of laziness…
Rounding pi to 3 is just the engineering way. It’s close enough to get the job done and then I don’t have to worry about decimal places. However, using pi=3 typically undershoots your calculations, so personally I like to use pi=4
An error margin of less than 5% (even better, biased in a known direction) is more than good enough for plenty of use cases.
An error margin of more than 25% on the other hand, is seldom acceptable.
Nah, it’s fine. Trust me I use pi=4 in every calculation I do that uses pi and I haven’t ever run into any issues at all
(I’m not that type of engineer, I never do anything with pi)
It’s called safety factor
One is an error margin, the other a factor of safety!
I finally found you, an engineer actually using π=3 (or 4 as you say), and not just people making fun of it.
I am also an engineer, but I’m going to wager much more recently graduated (worked 3.5 years).
Who hurt you?
Like, I get it, in a world before calculators, but there’s a button on the calculator, in your spreadsheet, in whatever program that approximates pi to many, many, many digits.
Putting in a design/safety margins into pi seems like a strange choice.
Sincerely, an engineer looking for answers on this π=3 meme.
Even if it’s back of the napkin first past approximation. You have a phone calculator. Please use it for our collective peace haha
(All jibes in jest, I’m genuinely curious)
Only 7 years of engineering experience and pretty much every time I have used pi, I have rounded it to 3 or 4. Now, the thing is, I am an electrical engineer that works in industrial automation. I never use pi at all
Doesn’t have the famous
ln(640320³ + 744)/√163
for some reason. Accurate to 14 decimal places I believe which is more accurate than what you need for 99.9% of its applications.
So to avoid memorizing a 15-digit number you’ll memorize a 13-digit equation?
More like you memorize that to show off. There are tons of high schoolers that know pi to dozens of digits, it’s not really exciting. But most high schoolers fundamentally don’t understand logs.
14 decimal places is more accuracy than you’d ever need.
Consider the size of what you’re measuring.
I’m American so you’re getting SAE units, deal with it.
If we have a radius of 1", the circumference of my object is 6.283185 or so inches around. Maybe it’s 6.283186. the difference between those two numbers is one one hundred thousandths of an inch. About 25 nanometers. Half the size of the smallest bacterium we’ve ever discovered.
That is with 6 decimal places. With 8 you can measure a circumference with an accuracy to the single atom. Any smaller than that, and you start charging the result by measuring it at all.
It’s been said that with 15 decimals, you can calculate the circumference on the observable universe with a precision of the width of an atom.
This is an exaggeration.
The universe’s radius is around 46.5 billion light years (around 4.4 * 10^26 meters), the error introduced of using 15 decimals of pi is around the order of 10^-16. Thus the error of calculating the circumference would be in the order of
8.8*10^26 * 10^-16 = 8.8*10^10 meters
Not quite, according to JPL https://www.jpl.nasa.gov/edu/news/how-many-decimals-of-pi-do-we-really-need/
15 decimal places, for Voyager 1 - We have a circle more than 94 billion miles (more than 150 billion kilometers) around, and our calculation of that distance would be off by no more than the width of your little finger.
It’s also been said that with Pi to just four decimal places you can accurately send a spaceship to one of our nearest neighbouring stars and arrive within one kilometre of your intended target.
In fairness, that was said by me, and I do tend to be full of shit.
Well, shit.
This guy beat me to it.
3.11
You could say he was all mixed up, and he didn’t know what (else) to do.
He bet on himself though
Every 5y/o is better at copying the Guinness World Records logo.
3.1 I hold the world record for memorizing the shortest length of pi decimals.
- Eat it.
you won after all
This guy engineers
_
I win!
I have memorized less digits: " "
Fewer.
Fixed it
If anyone is curious, I looked it up and The Guinness Book of World Records currently recognizes Rajveer Meena as the world record holder for Pi memorization. He recited 70’000 digits of Pi while blindfolded in about ten hours in 2015. I can’t even begin to understand how someone could actually do that.
I memorized 100 digits some years ago using physical memory. I would type the digits of pi on the numpad and memorize the movements of my hand, how it feels and which button goes when by position. Then when I would have to recite it, I’d imagine a numpad, move my hand and just say the number that corresponds to the imaginary button I’m pressing.
Don’t know if that could work for 70k digits though
Savant
I like how the filename is “NoFair.webp”. Hiding a funny little message in the filename is classy.
Pi for workgroups.
I hold 2 GWR for the Reddit Secret Santa.
Anyone that participated during a couple years qualified.
During lockdown I had a bit of time on my hands so I memorised all the digits of pi in the right order.
Hey, me too! I also did e and the Feigenbaum constant, though.
I memorized them in numerical order. First there’s a bunch of 0s then a bunch of 1s, followed by 2s, and so on.
Yeah but how many 0s do you have before you get to the first 1? I’ve been working on it but still don’t have a definite answer.
At least 4 or 5
I don’t know the exact number but it’s quite a few of them
Infinite.
Is that actually true or is that an unsolved problem?
It’s believed to be true to a high degree.
Pi is infinite. It’s also believed with a high degree of certainty (but not proven) to be a normal number, which basically means all the digits are evenly distributed over the infinite series. So if that is true, there would be an infinite number of 0s. Theoretically it could suddenly turn out to not be normal after a certain amount of digits are found, and then 0 could just stop entirely after a certain point, but this is incredibly unlikely.
I took the opposite approach. All the digits of pi, in the right order, are 3.145926870.
Obviously I had to eliminate any duplicates otherwise this post would have been a lot longer.
You should do alphabetical next.
right order
descending primes, right?
Decimal expansion. 3.14 etc
am I missing a bad joke here?
All… ALL of them?
Does anyone else really want to write them now just to get an official rejection letter?
If I write them enough and get enough rejection letters, can I then get accepted as the Guinness World Records record holder for most rejections of Guinness World Record records?
Is there a Guiness world record for classes or categories of individuals with the most rejection letters from the Guiness World Records association?
If you pay for it I’m sure they would gladly add it