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"At this very moment in the town of Couer d'Couers, young Ned was 9 years, 27 weeks, 6 days, and 3 minutes old. His dog, Digby, was 3 years, 2 weeks, 6 days, 5 hours, and 9 minutes old. And not a minute older."
For whatever reason, very intelligent people in fiction are incapable of summarizing anything. No matter what you ask them, you'll get exactly what you asked for
, with way
more detail than is necessary. No robot will ever say "it's pretty darned likely" or even "about one in 8000
that you'll fail"; they say "There is a 99.9875653 percent chance of success".
Common in Spock Speak
and Robo Speak
. Spock often estimated time in tenths (and later hundredths) of a second, which is of course useless as the sentence takes several seconds and there is no understood convention of exactly what instant that would refer to, even if one were capable of tracking time with this precision.
This happens most with numbers, but can show up in factual explanations as well. When you ask your Robot Buddy
if the air is breathable, odds are he'll go into more detail than you really need.
Note that in real life, the concept of significant figures
means that, depending on the circumstances, ending a number with a lot of zeroes is both intuitive and practical. Use of overly precise statistics
to verify claims will often be a sign of pseudoscience
rather than proper scientific method. This is particularly true when the statistics in question could not have realistically been measured to that degree (i.e. the margin of error is being ignored) or if they are subject to major fluctuation anyway.
This is very frequent in Exact Time to Failure
counts; this is largely because the more figures are shown, the faster the timer appears to be counting down. This, of course, lets the hero stop the timer at exactly 0:00:01
See also Mouthful of Pi
and Good with Numbers
. Often used by characters like the Clock King
. Sounds like, but is (usually) unrelated to, Improbable Aiming Skills
. And Ninety Nine Cents
is a trope that plays with this one. Compare to Your Days Are Numbered
open/close all folders
Anime & Manga
- L from Death Note is prone to giving exact percentage probabilities that Light is Kira. According to Word of God they were all made-up anyway, as any time he said this he was almost entirely sure of it.
- Yuki Nagato from the Haruhi Suzumiya series, who is a ridiculously human alien. Probably the prime example of her ludicrous precision is the "Endless Eight" arc, where she breathlessly tells the rest of the SOS Brigade exactly how many times the past two weeks have looped (Which is thousands of times, mind you) and how many times certain events did or didn't happen during these loops.
- In the Sky Girls OVA, Karen uses this to show that she is the team's Smart Guy.
- In Onidere, Tadashi has calculated how long he can hug his easily excitable girlfriend so that she stops crying, but doesn't pass out (7 seconds).
- At one point in Durarara!! Shizuo Heiwajima tells someone that there's a 0.0000000000000000000675% chance that you can kill someone with a glare before beating the shit out of him.
- Neon Genesis Evangelion manages to reconstruct this trope. They announce there are 32768 possible causes for the accident. Then, you realizes it was a Genius Bonus: exactly 2 to the 15th power. And then, because the estimation comes from Magi, you understand it's what computers (which use binary) will say instead of "thirty thousand".
- Playing the trope straight, Ritsuko will often give extremely low percentages of success (often something like 0.000234%) to the strategies NERV comes up with against the Angels. Naturally, they usually succeed. It's justified in that the top brass are secretly following prophetic documents, so they know the strategy will work, regardless of its conventional probability.
- Fushimi Saruhiko of K knows everything about Yata Misaki, including his height which is 167cm...well, 166.9 cm to be exact. The ludicrous precision stems from the fact that he knows even though Misaki himself doesn't know his own height. Played for Laughs but if you think about it, kinda creepy.
- One of the monster cards in Munchkin is "3,872 Orcs". Also, the rules include a time limit of 2.6 seconds for anyone to speak up after killing a monster.
- The Touhou Project fanvideo features Yamaxanadu Shikieiki convicting many Touhou characters of various crimes. One of them is Suika, who is accused for stalking Inaba since 100 million years and 2 weeks ago.
- At one point in the Naruto fanfic Time Braid, Sakura, who has picked up chakra-sensing abilities, says something to Naruto along the lines of "I can't help feeling that you're, um, two thousand, seven hundred and thirty times as strong as me."
- Kuyou Suou in Kyon Big Damn Hero counts time in "rotations", with each one taking about 1/1500th of a second.
- In the Pony POV Series, Twilight is able to time events to the point second in her head. She explains that some of the more complicated spells require that kind of mental precision in order to cast.
- Subverted in Terminal Justice when Mr. Black gives [[Comic Book/Batman Alfred]] "roughly 15 more years" to live. He can offer an exact amount of time but understands that Bruce wouldn't want to know.
Films — Live-Action
- Terminator 2: Judgment Day: After the good Terminator blows up several police cars, we see his heads-up display which shows "0.0 CASUALTIES". This doesn't make much sense no matter whether "casualty" is interpreted as "death" or "injured person": The former would imply there is such a thing as partial death, while the latter means that the Terminater blew up a number of cars with a minigun and a grenade launcher in such a way that not a single policeman suffered even a minor burn, cut, or bruise. James Cameron explained that they tried using a simple 0, but thought it looked silly, so the decimal was added per Rule of Cool.
- "87.4% of statistics are made up on the spot."
- A museum guide showing the visitors a fossilized dinosaur skeleton:
Guide: This dinosaur skeleton is 150,000,007 years, 5 months and 16 days old.
Visitor: How can you tell the age so accurately?
Guide: Well, it was 150,000,000 years old when I started working here, which was 7 years, 5 months and 16 days ago.
- A man hasn't been feeling well, so he goes to his doctor for a physical. Afterward, the doctor comes out with the results. "I'm afraid I've got some very bad news," the doctor says. "You're dying, and you don't have much time left." "That's terrible!" says the man. "How long have I got?" "Ten," the doctor says sadly. "Ten?" the man asks. "Ten what? Months? Weeks? What?" The doctor interrupts, looking at his watch. "Nine... Eight..."
- David Weber's Honor Harrington books are full of this. He often gives ship velocities to 6 significant digits, when those ships are accelerating at rates that make the last three digits change in the time it takes to read the number. On one occasion he had a character verbally give a "time to grav lance range" in hundredths of a second, and almost nobody in the series will say something like "about five minutes" when "two-hundred-ninety-three-point-two seconds" is more accurate.
- However, sometimes there are Ludicrous Inaccuracies, such as "four thousand KPH—make it sixty-seven KPS" in Echoes. Yes, KPH is kilometers per hour, and KPS is per second. And it is averted at least once, when the time to impact is stated as "170 seconds from... mark." Not that it's hugely important either.
- Played with in Sylvie and Bruno, when Bruno estimates that there are "about a thousand and four" pigs in the field outside. When told he can't possibly be sure about the "four" part, he insists that that's the only part he's sure about—there are four pigs right under the window, but he can't be nearly as precise about how many are in the rest of the field.
- Used in at least one version of The Hitchhiker's Guide to the Galaxy. Justified by Rule of Funny, and in particular in this case because it's coming from the narrator.
Many stories are told of Zaphod Beeblebrox's journey to the Frogstar. Ten percent of them are ninety-five percent true, fourteen percent of them are sixty-five percent true, thirty-five percent of them are only five percent true, and all the rest of them are told by Zaphod Beeblebrox.
- Used for the opposite effect in To Kill a Mockingbird. When asked by the judge during Tom Robinson's trial, Mayella Ewell gives her age as "nineteen-and-a-half." The fact that a nineteen-year-old still thinks of her age in halves serves to show that she doesn't get out as much as she should.
- In dialogue (internal or with other characters), Keith Laumer's Bolos always measure things down to hundredths of a second or less.
- In Going Postal, Mr. Pump the golem berates conman Moist von Lipwig for his criminal lifestyle, citing that although he's never used violence, the deprivation of his victims has cumulatively killed 2.338 people. Later, Moist questions the accuracy of this.
- Chapter 85 of Moby-Dick deals with the question of whether the whale's spout is water or vapour, a question which has lasted from the beginning history until
this blessed minute (fifteen and a quarter minutes past one o'clock P.M. of this sixteenth day of December, A.D. 1851)
- In The Waste Lands, Blaine (a sentient monorail train) can tell if someone is lying using voice analysis, which he claims has a reliability of 97% plus or minus 0.5%.
- In Momo, one of the grey men giving his age. Justified, since they're not human.
- One article in the Annals of Improbable Research researched the question "how much wood could a woodchuck chuck if a woodchuck could chuck wood," and concluded that "Marmota monax is able to chuck wood at a rate of 361.9237001 cubic centimeters per day."
- In John R. Powers' fictionalized memoir The Last Catholic in America, the narrator, Eddie, tells us about his class's eighth-grade "sex talk" delivered by one of the parish priests. The priest lays this one on the class:
"Furthermore, boys, it has been estimated that more people go to Hell because of sins of impurity than for any other kind of sin. Perhaps as many as two out of every three people who go to Hell go there because of the sin of impurity. "
- Used to enhance a Badass Boast by the Makuta in one of the BIONICLE novels:
"... but we both know that there are a thousand ways I could destroy you right now. And 941 of them hurt."
- Many, many films and series give way too exact estimates of oxygen supply or poison effects. Both can easily vary by a factor of 2 if not more.
- Doctor Who: K-9 is prone to this, even needing to be snapped out of infinite repetition when a percentage goes into "three... three... three... three..."
- In the new Knight Rider, Michael is poisoned. KITT has a countdown to his death that goes into the hundreths of seconds.
- KITT would do this in the original too (though rather less ludicrously), by giving distances to the tenths place, correcting times if they were a minute off, etc.
- Star Trek:
- Vulcans in general are gung-ho for this trope.
- Star Trek doesn't just do it with numbers, either. Whenever they discuss an order or regulation, it isn't enough for them to cite the regulation's number, they also know the applicable section and paragragh. While most modern-day servicemembers are fairly well-read in terms of their branch's regulations, not many can tell you which paragraph the relevant information is found in off the top of their head. Sometimes justified by them looking up the regulations ahead of time.
- In the original, Spock did this all the time, even in situations where the precision of his calculation was obviously not just unnecessary, but impossible. Lampshaded in "Errand of Mercy":
Kirk: What would you say the odds are on our getting out of here?
Spock: Difficult to be precise, Captain. I should say approximately 7824.7 to 1.
Kirk: ... "Difficult to be precise"? "7824 to 1"?
Spock: 7824.7 to 1.
Kirk: That's a... pretty close approximation.
Spock: I endeavor to be accurate.
- Data, from The Next Generation, regularly practiced this during the show's first season, and was hushed nearly every time. Since then, he'd learned that most people don't really care for specifics of such length. Being an android, data can count all the seconds.
6 days, 13 hours, 47 minutes. Riker:
What, no seconds? Data:
I have discovered, sir, a certain level of impatience when I calculate a lengthy time interval to the nearest second. [beat
] However if you wish... Riker:
No. No. Minutes is fine.
- From Deep Space Nine:
- Bashir became insufferable for this after it was revealed he was genetically engineered. Even his actor hated it. He provides the likelihood of the success of the Dominion in the Dominion War to two decimal places. For reference, the Dominion War was a massive conflict involving four of the most powerful organizations in the galaxy. He also used this trope to calculate travel times in a damaged ship faster than the computer could, despite it making no sense for him to be able to calculate this without being some kind of warp-travel/impulse-travel expert, never mind it being an enemy ship they barely understood the workings of in the first place. It was even lampshaded by characters in-universe how unnatural he was being. It didn't stop the writing staff from continuing to do it, however.
- This trope was Lampshaded in Deep Space Nine's "Take Me Out to the Holosuite":
Sisko; It's been a long time.
Solok: Ten years, two months, five days.
Sisko: You mean you don't know it to the minute?
Solok: Of course I do. But humans are often irked by such precision. Especially the more emotional humans.
- From Voyager:
- An odd variation occurs in "Imperfection". Tuvok scans a destroyed Borg Cube and announces the presence of approximately 37 Borg drones. Paris immediately states that such an even number does not sound like an approximation. Tuvok then has to clarify that he's not counting bodies, but body parts.
- Defied in one episode that dealt with Janeway taking a group of lesser known crew members on a away mission to get to know them better. One of them admitted that she has a really hard time keeping up with all the insane calculations and tech stuff that comes second nature to everyone else. In the climax of the episode they were racing away from a shockwave and she counted down the seconds until it hit them, when she reached zero everyone flinched preparing for impact. When nothing happened they all looked at her and she said "More or less." and then the shockwave hit them.
- In Enterprise, "Hull integrity" is just their replacement word for shields, which would lead to the ship being just fine until it hit 0%. Although components, like warp and weapons can fail at a much earlier time, and as soon as the shields are down, they usually get boarded.
- The Big Bang Theory
- Sheldon Cooper. Ask him a simple question and you'll get a lengthy dissertation, mostly on how wrong you are. And sometimes he'll give it to you even if you don't ask. Often, said dissertation merely explains how the question is badly formed or predicated on erroneous assumptions.
- While Sheldon is the worst offender, the other characters (except Penny) do this, too. Leonard discusses a kiss with Leslie: "Well, the Earth didn't move. Except for the 383 miles it was going to anyway."
- Spencer Reid in Criminal Minds does this all the time, much to his teammates' annoyance. Lampshaded at one point:
Reid: With this type of criminal, all are angry, most are male, and few, if any, are ever caught.
Elle: Few, if any? You don't have the statistics on that?
Reid: 6%. I'm trying to be more conversational.
Elle: Oh. It's not working.
- The narrator in Pushing Daisies always does this when giving the age of a character.
- JAG: Despite not wearing a watch Mac can tell you what time it is, or how much time has elapsed, no matter what the situation is. She says that she's usually accurate to within 30 seconds, and when people ask her how she does it she just says "It's a Marine thing."
- One of M2M's song, Everything, has this line:
It's been nine days, eight hours, forty minutes, ten seconds, since you called
- Journalists are very prone to treating opinion polls as more precise than they really are. The time before any election will see many such cases. For example, if one particular poll suggests candidate A has 43% support while candidate B has 41%, many newspapers will quickly conclude that A is leading. This ignores the fact that even the most scientific polls will often have a 3% margin of error. See the Fallacy Files for several examples. A more in-depth view of the phenomenon can be found here.
- And not understanding notions of margin of error and significant digits generally. Expect 3000 K to become precisely 5923.4 °F.
- If there's a chart, it won't have error bars. Ever.
- The Daily Mail (the British newspaper which caters for the tinfoil-hat brigade) once ran an anti-SI-units article claiming that Britain would soon have to face "31Ľ" MPH speed limits. Apart from the error of assuming that the rule-of-thumb conversion (8 kilometres approximately equals 5 miles) is an exact one (the correct conversion of 50km, to the same four significant figures, is nearer 31.09 miles than the stated 31.25), they also failed to realise (or willfully ignored) the fact that the percentage difference between 30 and 31.25, let alone that between 30 and 31.09, is well within the tolerance of mechanical speedometers. Plus there's the fact that if they'd used the other rule-of-thumb conversion (5 km approximately equals 3 miles), the whole basis for the silly article would have disappeared.
- One newspaper article once claimed that a "hundred thousand ton" ship displaced "101,605 kilograms". Apart from having an error of three orders of magnitude, this also assumed that the displacement was known to the nearest pound. (It also didn't follow SI standards; it should have been "100 Gg".)
- Sprint times in professional sports are frequently measured to thousandths of a second by stopwatches operated by human hands—which are not precise to such small degrees. Worse, differences of a few thousandths or even hundredths of a second in dash times are often touted as being very significant, when, practically, differences of less than a tenth of a second in distance dashes are close to no difference at all.
- The funny thing is, in tabletop games, one often can calculate the odds of success to a very high precision (though it's still not perfect since even well-made dice have slight imperfections).
- Percentile-based resolution mechanics in particular can edge into this. Most real or fictional people won't ever be able to estimate their own or anyone else's "skill rating" or other overall performance to even such a level of precision as "Stealth 43%" — and yet, there you get it listed right on the character sheet.
- Feng Shui: The Gambler Archetype has this as its Unique Schtick.
- Played for laughs in Metal Wolf Chaos where Jody flat-out guessing it will take the Alcatraz Cannon four minutes to recharge turns out to be accurate to the nearest hundredth of a second.
- Lampshaded in Space Quest 6:
Once the Divalium crystal has been repaired, our electrical system re-established, and the engines fired, I am 97.2 percent certain [that the spacecraft can continue on its way]. Roger Wilco:
Why only 97.2 percent? Manuel Auxveride:
I judged 97.2 to sound more hip to our audience than would 100. You would have to mention it. Roger Wilco:
Sorry. Manuel Auxveride:
Don't apologize to me. It's the players you ruined it for.
- Pokémon: The American version of Pokédex entries are known for this. Instead of making up new measures for some of the Pokémon, the localizers decided to simply convert the metric to imperial, resulting in all small Pokémon being lumped into measurements of either 4 inches, 8 inches, 1 foot, 1 foot 4 inches, etc. And in the case of temperature: "Regice cloaks itself with frigid air of negative 328 degrees Fahrenheit." In Japan, it's -200 degrees Celsius.
- In Spirited Heart, when demon Child Prodigy Hade gets selected to become a scientist at the King's Royal Laboratory, one of the teachers notes that she is at least forty years younger than the previous youngest researcher. She corrects the teacher by saying that she's the youngest by exactly "Forty-seven years, six months, and two weeks".
- Fi, the local Exposition Fairy of The Legend of Zelda: Skyward Sword, loves to throw out percentages any time a possibility arises. Though the numbers are a lot broader than other examples on this page, always a multiple of 5, she still gives them in uncertain situations when such probabilities should be incalculable. As with most examples of this, the suggested possibility is always the case, even though Fi gives probabilities ranging from 40% to 95% (never 100%). Apparently she's not very confident, even though she's always right.
- She does use an absolute one time, however: when you are about to enter Demise's realm, Fi tells you there is a 0% chance of you returning unless you are able to defeat him. The fact that she almost never uses absolutes makes it all the more chilling when she does.
- In a more comical time, the only other time she uses an absolute (100%) is when she is calculating your chances of being irritated by a crow pooping on your head.
- The World Ends with You
- Sho Minamimoto. Seriously, the incantation he uses for his ultimate attack is reciting 156 digits of pi, rightfully earning him, at least at time of writing, the page image for Mouthful of Pi.
- Konishi also gives the exact amount of time Sho's late to a meeting when he's first introduced.
- While not appearing in the games themselves, Touhou's Renko Usami has this with her ability to read the time from the stars, right down to the second at the very least. It's assumed her accuracy when getting her location from the moon is just as precise.
- Admiral T'nae of Star Trek Online has a habit of stating probabilities that something will happen in percentages out to two decimal places.
- Girl Genius is about Mad Scientists, so it should be expected:
Agatha: (about an overdose of funny water)
I believe another forty-five point three seconds, and I would have exploded
- In Bob and George, during the Fifth Game arc, Mega Man wonders who the next master is (after he had cut Gyro Man to ribbons), and then come to a card that says "Crystal Man" and the odds of it answering Mega Man's question; 1 in 2^24,036,583.
- In Worm, Dinah Alcott's predictions of the future often feature percent probabilities to five decimal places.
- Several of the creepypastas featured in Retsupurae's Crappy Pasta series tend to be rather specific about time, producing such sentences as "This continued for 25 seconds" or "I sat there for maybe 25 seconds, horrified by what had just happened." Even funnier, the times themselves are often implausible, like spending 10 minutes running Mario down a featureless corridor.
- In Brennus, Brennus and Polymnia give ludicrously precise measurements for the depth of the Diggerer's tunnel (1.121134 miles beneath sea level). Exposed's blog gives her measurements as 1.71837468991 meters tall and weighing 78.22223485771 kilograms.
- In Tales From My D&D Campaign, the heroes learn that if they engage Lord Kintemazu, he will kill exactly 1.5 of them. This seriously creeps the heroes out as they try to figure out how he could know the outcome of a combat so accurately.
- The UK Staples website lists some office chairs as having a maximum loading of "110 kgs[sic]" or "17.25 stone". Apart from the question of what on earth a kilogram-second is supposed to be, one also has to wonder whether those extra 3.5 pounds really make any difference.
- Dnerd in The BOTS Master often spouted off really precise statistics, though this took a backseat to his being completely incapable of carrying a standard conversation.
"Calm down, Dnerd, it's just playacting."
"Playacting? Playacting is a compound intransitive verb..."
- In one episode of The Simpsons, Homer hears that the average man lives to be 76.2 years old, exclaiming that he's 38.1 years old. The best part is that he's wrong — he's 39.
- This is J. Jonah Jameson's gimmick in The Spectacular Spider Man. "I want that report in 18 seconds!"
- Exploited in an episode of The Adventures of Jimmy Neutron: Boy Genius, when Jimmy came up with an idea to get rid of his robotic servants on a mission to "correct error" who had reasoned humans are inherently extreme errors that must be deleted. When Jimmy said pi equals 3, the robots tried to correct him, exploding before they achieved Ludicrous Precision.
- The Angry Beavers: Daggett achieves this while hiding under the floorboards.
Daggett: A bug... two bugs... four bugs... (explodes out through the floor) AAAAH! 4023 BUGS!
- Ron in Kim Possible goes through an entire episode like this, despite not being the brainy one... he just took a big interest in his dad's work (Mr. Stoppable is an actuary).
- In the My Little Pony: Friendship Is Magic episode "Fall Weather Friends", Pinkie Pie is commentating on the Running of the Leaves, and at one point she tries to figure out exactly how far ahead of Applejack Rainbow Dash is:
Pinkie Pie: She's ahead by half a nose! Or maybe three-quarters of a nose! No, about 63.7% of a nose! (sees Spike staring at her) ...Roughly speaking.
- The Star Trek TOS example above is spoofed in Muppet Babies, where Gonzo (as Spock) takes so long to say the fractions on the odds that he has to be cut off by someone.
- In an episode of The Real Ghostbusters, the heroes are in a castle that is being beseiged by an army of skeleton warriors. Venkman wonders how many their are, and Egon counts out the exact number. Venkman quickly tells him he didn't really want an answer.
- One of the characteristics of the Clock King in Batman: The Animated Series.
Temple Fugate: Thirty-seven pages? That would take a copier exactly one minute and 49 seconds. One more delay like this and you're fired!
- An episode of Stingray1964 had the villain torturing Marina by slow electrocution. According to the dialogue, for her species the difference between a non-fatal and a fatal dose is very precisely defined, and is only a few volts.
- Parodied in Archer, where one episode begins with Cyril trying to present a report where he insists on using metric units, which Archer and Mallory both complain about. From then on in the episode, they always replace to any approximate or idiomatic use of units to exact metric conversation, like Archer making a "firm 12 inch" joke and sarcastically correcting himself with ".305 meters".
- This is the default display mode for floating point numbers in computers. And given that floating point numbers tend to be wrong by some billionth, you usually end up with way more decimal places than needed.
- The "normal" body temperature of humans is often given as 98.6 degrees Fahrenheit. This is due to an adjustment to the original scale to a more precise division. It was originally based the freezing point of water (30 degrees by the previous scale he was basing his on) and human normal body temperature (90 degrees by the older scale). He adjusted it to 32/96 to make 64 intervals between the two. It was later adjusted again to make the freezing and boiling points more precisely 32 and 212, respectively, making body temperature 'about' 98.
- Alternatively, it's what you get when you convert 37.0 degrees Celsius to Fahrenheit.
- Or convert 37 degrees Celsius (noting that body temperature can vary by around half a degree over the course of a day) and retain the spurious precision.
- Film box office figures (specially for recent productions) only lack cents to be more precise.
- John Stossel (Myths, Lies, and Downright Stupidity) reported in one of his books how the average weight of a bird was given in grams to one decimal place. This was done by converting the real estimate from Imperial to Metric and adding "drama digits." The real estimate was "about half a pound." It just goes to show what significant digits are for.
- When combined with "Blind Idiot" Translation, this trope may lead to interesting conversions where a person may proclaim that something is e.g. "approximately 9.144 meters away" or "weighing at least 90.718474 kilograms".
- Some translated cookbooks originally using Fahrenheit scale will tell you to set your oven at a Celsius temperature of 1 degree precision, or vice versa.
- The above two problems led to a fair amount of bafflement with American editions of some of Phaidon's cookbook line, especially their stupendously popular Silver Spoon books; since Phaidon frequently doesn't include metric measurements in their American editions, you will frequently be asked for the seemingly random quantity of 2 1/4 lb (~=1kg) of something. Ironically, some of their less-popular books retain the metric measurements across national editions, eliminating the problem.
- The recipe for IKEA cream sauce (for their Swedish meatballs) has a similar issue: it was obviously written for metric measurements, as the recipe in America calls for 1 1/5 (!) cups of water. 1/5 cup is not a usual measurement in Amercian cooking (divisions are usually by powers of two, or by thirds), making measurement of this amount problematic. 1 1/5 cups converts to ~283 mL, meaning the original measurement called for was probably 275 or 280 mL.
- ...a fine demonstration of this trope in action! The original was 300ml, using the realistically imprecise conversion of 1 cup = 250ml.
- Guinness claims the perfect double-pour of its draught beer takes 119.53 seconds. Apparently if you take that extra .47 seconds for an even 2 minutes you've ruined your beer entirely.
- In the hard sciences (especially physics and chemistry) the use of significant digits is a necessity to correctly reflect the variations between measuring devices and to understand the meaning of the margin of error (and use it). If you are measuring something to the thousandth decimal place, having a reading that just goes to the tenth decimal place is an incongruity (if you are using the same device you can't have both .005 and .05 as measurements, the second number has to be .050 or something with that added decimal place). All that said, unless you are going into something like particle physics there is almost no real world need to be that precise (i.e. a house isn't going to collapse if you are .5 cm off on the span of a beam). This is also part of the reason a lot of old-line engineers miss slide rules — taking calculator results too literally frequently leads to false precision when it isn't needed. However, besides physics, in classical analytical chemistry (i.e., the kind that nobody does anymore since the advent of spectrometry and spectroscopy methods: gravimetry, titrations, potentiometric analysis etc.) high precision is vital if it's a quantitative analysis. Same goes for reagent masses in synthesis. Yes, it can really make a difference if you use 0.572 instead of 0.579 g of a reagent.
- Football (soccer) suffers a bit from this as the rules were originally written in Imperial measurements but are now administered in Metric units. For example the goals are specified as being 7.32m x 2.44m, that being the equivalent of the old eight yards wide by eight foot high.
- Engineers or students with no practical experience often fall prey to this, because they still think of their results as mathematical abstractions.
- This trope has been blamed for the failure to get Americans to use the SI system back in the 1970's. When told they had to learn and calculate multi-digit conversion factors, they instantly despised the whole idea. Ironically, they now happily buy 2-liter soda bottles, run 5K races, and shoot 9-millimeter bullets, because some smart marketers realized that the conversions were irrelevant.
- Deliberately invoked with the calculation of the highest point of Mount Everest, known as Peak XV. Its height, calculated by the Great Trigonometric Survey as the average of several independent measurements, came to exactly 29,000 feet. Two extra feet were then arbitrarily added, bringing the official height to 29,002 feet, so that the value did not look like a rounded estimate.
- The most basic units in the International System of Measures are defined in this way: a meter, for instance, is equal to the distance that light travels in precisely 1/299,792,458 seconds. For that matter, a second is exactly the length of time it takes for a particular isotope of caesium to oscillate between two states 9,192,631,770 times. This was done instead of rounding off so that the units (which are actually pretty arbitrary) would be of the same magnitude both before and after their redefinitions. The only unit which is not defined this way is the kilogram, though ironically, the mole subverts this: a mole is a group of atoms equal in number to the Avogadro constant, which itself has only 11 significant figures out of a possible 23, meaning that two moles of the same substance could have a difference of as many as two trillion molecules or atoms between them.
- The doctrine of comparative responsibilitynote in American law has gotten kind of weird on account of this trope. Comparative responsibility allows a negligent plaintiff to recover in an action in negligence; the simplest and probably most common example is between two drivers, both driving unsafely but with one driver being more unsafe than the other (e.g. Alice running a red light and going 15 over the speed limit vs. Bob just going 10 over). The general rule in comparative responsibility is that the less negligent party can collect from the more negligent one, but the amount the less-negligent plaintiff can collect is less than if he/she was completely innocent. All of this is a simplification; the actual details of the doctrine can get annoyingly convoluted. In Britain, the strange and complex rule worked OK, because Britain had already abandoned jury trials in most civil cases, but in America the civil jury trial remained alive and well. This created a problem—how to explain the rule to the jury, which is of course composed of people who don't know the first thing about torts law? Judges decided that in they would tell juries to assign a percentage amount of fault. This was intended to be a rule of thumb, with juries expected to give answers in nice round numbers (eg. 60/40, 80/20, what have you). Instead, we find juries assigning fault in amounts like 43.75/56.25note or even 68.94/31.06note
- The former ratio is an excellent example of conversion making a number look more precise than it actually is; 43.75:56.25 actually reduces to 7:9.
- Back before digital watches, little kids learning how to tell time would usually correct their parents when mom or dad rounded off time to the nearest 5-minute increment. Part of growing up/losing one's innocence was finding out that there is usually no significant difference between "ten till five" and "4:52."
- In the work world however you better believe a difference of two minutes clocking in or out makes a difference for many jobs, enough that an employee can get disciplined or even fired, so the kids may be right in this case.
- So far one of the few practical applications for ludicrous precision that many people take for granted is GPS. A GPS receiver uses the differences in time it received radio waves from the satellites to triangulate position. The thing is, the clocks in the GPS have to be really, really accurate, on the order of being within 50ns of each other. The reason is because since you're using how long it took for the radio waves to travel (which travel at light speed), if they're off even by a microsecond, the position can be over 300 meters off. It's actually even worse than it sounds, since at that precision it has to account for both general and special relativity as well.
- One convenience food packet instructed users to use "18 fl. oz." or "511 ml" of water in cooking it. Whilst accurate conversions of each other, neither measurement is achievable using a kitchen measuring jug; at that end of the scale, the divisions are usually to the nearest 5 fl.oz. or 25 ml. It would have been more reasonable to say 20 fl. oz. or 500 ml.
- In Quantum Electrodynamics (the quantum mechanical theory of electricity and magnetism), the measurement of something called the fine structure constant has an uncertainty of only around 1 part in a hundred million