# Unexpected precision **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [March 11, 2021, 5:07pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720 "2021-03-11T17:07:38Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Limmin](https://avatars.discourse-cdn.com/v4/letter/l/f04885/32.png) [@Limmin](https://boards.straightdope.com/u/Limmin)\ **Post date:** [March 12, 2021, 9:14pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/21 "2021-03-12T21:14:44Z")
> [@Thudlow\_Boink](#): > > > [@MoonMoon](#): > > > > another store counts “1” as a bunch of bananas > > Is there a specific number of bananas in a “bunch”? How precise is the statement “Yes, we have no bananas, we have no bananas today!” ---
**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Post date:** [March 12, 2021, 9:52pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/22 "2021-03-12T21:52:44Z")
Reminds me of the Mitch Hedberg joke: “I heard MTV’s Real World got 40,000 applications this year. That’s amazing man. Such an exact number.” ---
**Author:** ![gdave](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gdave/32/3683_2.png) [@gdave](https://boards.straightdope.com/u/gdave)\ **Post date:** [March 12, 2021, 10:04pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/23 "2021-03-12T22:04:30Z")
> [@Just\_Asking\_Questions](#): > > The episode that turned me off Mythbusters - they myth was that putting water on a greasfire would shoot flames “twenty feet” into the air. The experiment has flames shoot 18 feet. Myth “busted”. Yeah, right. Did they actually think the myth was 20.000000000 feet? I don’t remember that specific episode, but that seems out of character for them. Normally, with a result like that, they’d rate it “Plausible”. Maybe it was early on, when I think they only used “Confirmed” or “Busted”? If so, that myth was probably one of the reasons they added the “Plausible” conclusion. Even early on, though, they’d usually have a narrative caveat before “stamping” the conclusion, something to the effect of, “Technically, the myth as specifically stated is Busted, but the general idea is Confirmed.” ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [March 12, 2021, 10:23pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/24 "2021-03-12T22:23:46Z")
I’ve noticed the weather app on my phone has gotten oddly precise with its precipitation predictions. It literally says there’s a 1% chance of rain tomorrow. For purposes of planning my weekend, that’s effectively zero chance of rain. I don’t need to know that their computer model came up with some small non-zero probability. Just round it down to zero. Likewise I don’t need to know that there’s a 47% chance of rain on Sunday. Just round it to 50%. Really, IMO for communicating weather forecasts to the average layperson, rounding to the nearest 10% is sufficient. Any additional precision doesn’t provide any additional value to the average Joe who just wants to know if he can have a cookout this weekend. ---
**Author:** ![Bonum\_Legatum](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bonum_legatum/32/6183_2.png) [@Bonum\_Legatum](https://boards.straightdope.com/u/Bonum_Legatum)\ **Post date:** [March 12, 2021, 10:32pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/25 "2021-03-12T22:32:03Z")
Old story: Surveyors measured the height of a certain mountain _very carefully_ and came up with exactly 30,000 feet. But they put it in the records as 30,001 feet, because no one would ever believe 30,000. “Measure it with a micrometer, mark it with a crayon, cut it off with an axe.” ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [March 12, 2021, 10:38pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/26 "2021-03-12T22:38:23Z")
You’re probably remembering Andrew Waugh’s 1856 measurement of Mt. Everest, which came to exactly 29,000 feet, but was publicly declared to be 29,002 feet to avoid the impression that it was a rounded value. The currently accepted value is 29,032 feet, and the height is the subject of a somewhat humorous dispute between China and Nepal. China says the height should be calculated to the height of the highest point of rock, while Nepal wants to include the snow on top of that. ---
**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\ **Post date:** [March 12, 2021, 10:49pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/27 "2021-03-12T22:49:01Z")
Everest is also growing due to plate tectonics. The current estimate is that it’s getting taller at a rate of 4mm per year so it’s now about two feet higher than Waugh’s measurement. ---
**Author:** ![EinsteinsHund](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/einsteinshund/32/8400_2.png) [@EinsteinsHund](https://boards.straightdope.com/u/EinsteinsHund)\ **Post date:** [March 12, 2021, 11:54pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/28 "2021-03-12T23:54:38Z")
Isn’t there some erosion by more and more climbers (and by wind and weather, of course), working against tectonic growth? ---
**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\ **Post date:** [March 12, 2021, 11:56pm UTC](https://boards.straightdope.com/t/unexpected-precision/937720/29 "2021-03-12T23:56:52Z")
Not mentioned [here](https://economictimes.indiatimes.com/magazines/panache/indian-mathematician-radhanath-sikdar-first-to-identify-everest-as-highest-mountain-peak/articleshow/47496440.cms) so the 4mm/year presumably takes erosion into account. ---
**Author:** ![blabbermeister](https://avatars.discourse-cdn.com/v4/letter/b/e9a140/32.png) [@blabbermeister](https://boards.straightdope.com/u/blabbermeister)\ **Post date:** [March 13, 2021, 1:30am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/30 "2021-03-13T01:30:58Z")
> [@Hampshire](#): > > Reminds me of the Mitch Hedberg joke: > “I heard MTV’s Real World got 40,000 applications this year. That’s amazing man. Such an exact number.” Another oldie: A guide is giving a tour of a science museum. He points to a dinosaur bone and says “This dinosaur bone is a hundred million and three years old.” Someone asks him how he knows the age so precisely. He says “Because when I started working here three years ago they told me it was 100 million years old.” ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [March 13, 2021, 1:43am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/31 "2021-03-13T01:43:50Z")
I’ve mentioned it before here but there are a few road signs around here of the format “Sidewalk ends in 1090 feet”. As if there were lot of people who would have otherwise thought “damn! I thought I was going to be able to walk that extra hundred feet to the bar, since I could see ahead of me that it was 1190 feet, but now I have to subject myself to the grass and dirt!” ---
**Author:** ![gdave](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gdave/32/3683_2.png) [@gdave](https://boards.straightdope.com/u/gdave)\ **Post date:** [March 13, 2021, 2:03am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/32 "2021-03-13T02:03:34Z")
There is a G.E. facility which I have to drive through fairly frequently. They have a lot of speed limit signs posted. They used to say “SPEED LIMIT 25 MPH”, but a couple of years ago they started replacing them all with signs saying “SPEED LIMIT 24.5 MPH”. That extra 0.5 MPH was creating some significant safety hazards, I guess. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [March 13, 2021, 2:09am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/33 "2021-03-13T02:09:10Z")
> [@gdave](#): > > There is a G.E. facility which I have to drive through fairly frequently. They have a lot of speed limit signs posted. They used to say “SPEED LIMIT 25 MPH”, but a couple of years ago they started replacing them all with signs saying " **SPEED LIMIT 24.5 MPH"**. That extra 0.5 MPH was creating some significant safety hazards, I guess. - Velocity of Bond. That’s .007 miles/second. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [March 13, 2021, 2:33am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/34 "2021-03-13T02:33:09Z")
Vulcans make terrible butchers. ---
**Author:** ![blabbermeister](https://avatars.discourse-cdn.com/v4/letter/b/e9a140/32.png) [@blabbermeister](https://boards.straightdope.com/u/blabbermeister)\ **Post date:** [March 13, 2021, 2:43am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/35 "2021-03-13T02:43:15Z")
> [@gdave](#): > > There is a G.E. facility which I have to drive through fairly frequently. They have a lot of speed limit signs posted. They used to say “SPEED LIMIT 25 MPH”, but a couple of years ago they started replacing them all with signs saying “SPEED LIMIT 24.5 MPH”. That extra 0.5 MPH was creating some significant safety hazards, I guess. That could be smart: you slow down to read the sign - does it really say “24.5”? You slow down from 35 mph to look at whether your speedometer is graduated that precisely… Could it possibly be intentional? If so it’s smart. Unless you crash into someone while looking at your speedometer. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [March 13, 2021, 3:57am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/36 "2021-03-13T03:57:20Z")
Yes, there’s a speed limit sign on a winding mountain road near me that’s posted 17 MPH for exactly that reason. It draws the drivers’ attention more than a 15 MPH or 20 MPH sign would. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [March 13, 2021, 4:22am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/37 "2021-03-13T04:22:09Z")
> [@markn\_1](#): > > I don’t need to see the exact number of atoms I’m getting. To facilitate good comparison shopping, quantities of things like ground beef and bananas should all be given in moles. > [@wolfpup](#): > > I always get a kick out of news stories that convert from metric for the benefit of USians. Like “the explosion hurled debris up to 20 meters away (65.6168 feet)”. Never mind bringing metric into the picture. Try converting between statute miles and nautical miles. 1 nautical mile ≈ 1.15078 statute miles ≈ 6076.12 feet. 1 statute mile ≈ 0.86898 nautical miles. Nautical miles are used at sea and also commonly used in aviation. They are actually much easier to work with than statute miles, because the distance of 6076.12 feet is close enough to 6000 feet for most practical usage, and this makes feet ← → nautical miles conversions very easy to work with. ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [March 13, 2021, 4:59am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/38 "2021-03-13T04:59:42Z")
I’ve noticed the standards of measurements are “Hoover Dams” and “Titanics” ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [March 13, 2021, 7:17am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/39 "2021-03-13T07:17:50Z")
I have noticed that on the “Snowpiercer” series they frequently make reference to the length of the train. It started out as 1001 cars. Now that the Big Alice train has joined them they always say “1034 cars”. You would think “Here is all of humanity - stuffed into 1000 cars” would be good enough. ---
**Author:** ![Terminus\_Est](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terminus_est/32/3087_2.png) [@Terminus\_Est](https://boards.straightdope.com/u/Terminus_Est)\ **Post date:** [March 13, 2021, 8:05am UTC](https://boards.straightdope.com/t/unexpected-precision/937720/40 "2021-03-13T08:05:48Z")
Body temperature in Fahrenheit is always stated as 98.6°F. It’s not 98°F or 99°F. No, no, that 0.6° is very important. [Previous page](https://boards.straightdope.com/t/unexpected-precision/937720.md?page=1) [Next page](https://boards.straightdope.com/t/unexpected-precision/937720.md?page=3)