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Writers Cannot Do Math

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In Super-math it may be 32,000. But in regular math, it's 3,200.note 

Up in the sky, the alien mother ship sent down twenty hundred troops, three in each space jet.
And if you want to know how many jets there were, you can do the math yourself. I'm a very busy writer trying to make a movie here.
Calvin and Hobbes II: Lost at Sea (a Script Fic that imitates a movie)

You're watching a show or movie, or reading a book, when suddenly something numerical throws you for a slight curve — like a date, or a character's age. Your brow furrows. You start ticking things off on your fingers. What the hell? That wasn't right!

You have just discovered the fundamental truth: that your favorite author failed irredeemably at high school math and never wants to see a number ever again except in the corner of a page. This is a particular kind of continuity error that would be avoided if professional writers kept calculators at their desks. It can also come from multiple writers not checking with each other, or screwups in the timeline.

Compare Soap Opera Rapid Aging Syndrome, Not Allowed to Grow Up, and Longest Pregnancy Ever, where the writers can do math — they're just intentionally fudging it. See also Sci-Fi Writers Have No Sense of Scale and Not Drawn to Scale. Possibly the root cause of Everybody Hates Mathematics. Might even involve E = MC Hammer. Artistic License – Statistics is a subtrope.


A natural habitat of the MST3K Mantra and Fan Wank, as in many cases, these errors are not important for the plot (even when they are).

Oh, for the examples below that reference the number Pi, it is an irrational number with no limit — an endless number — of digits, but the first 16 are 3.141592653589793. Also, the first thirty-two for the square root of pi are 1.7724538509055160272981674833411.



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    Comic Strips 
  • The Dick Tracy story "The Man of a Million Faces" features a string of bank robberies committed by celebrity lookalikes — or is it a single master of disguise? The story makes a big deal of using known heights of objects to measure (they mean "calculate") the perpetrator's height, which turns out to be a consistent 5'11". Yet a previous diagram shows a line labeled 69.9" going over his head with room to spare.
    • Presumably the writer forgot that there were 12 inches to a foot, not 10.
  • Another Dick Tracy story involves thieves stealing small-valued coins from parking meters. Now, $2 in nickels is only 40 coins, far less than the large handful shown, whereas when Larry throws $20 in pennies onto his mother's stomach, the size of the bag pictured is about right, but that would seriously hurt.

  • The song/story "A Billion Baseballs" by the Green Chili Jam Band does multiple calculations related to these baseballs and gets almost all of them wrong. For example, it says that this many baseballs placed on the ground would take up a giant square "eighty miles around." Since baseballs are three-inch diameter objects, a square of 31,623 by 31,623 baseballs would have a perimeter of under six miles.
  • Foxy Brown's verse on The Firm's "Affirmative Action" contains this horrible bit of addition:
    We gotta flee to Panama, but wait it's half-and-half
    Keys is one and two-fifth, so how we flip
    Thirty-two grams raw, chop it in half, get sixteen, double it times three
    We got forty-eight, which mean a whole lot of cream
    Divide the profit by four, subtract it by eight
    We back to sixteen, now add the other two that 'Mega bringin' through
    So let's see, if we flip this other key
    Then that's more for me, mad coke and mad leak
    Plus a five hundred, cut in half is two-fifty
    Now triple that times three, we got three-quarters of another ki
  • The Shooter Jennings concept album "Black Ribbons" is set in a not-too-distant future dystopia. The narrator, the Will 'o the Wisp, makes reference to a real book published in the 1970s, stating it was written forty years ago, putting the date around 2010, when the album was released. This could be a case of a changed past, but then he mentions Obama's election and says everything went to seed after that. Either Obama's term was cut short, or the math is wonky. This is made worse by the fact that Stephen King wrote the narration.
  • The Rage Against the Machine track "Down Rodeo" includes the classic hook: So now I'm rollin down Rodeo with a shotgun / These people ain't seen a brown-skinned man / since their grandparents bought one. Even if the song is describing a 1960s Black Panther, which the lyrics seem to suggest, that's over a century since the end of slavery, making it extremely unlikely that anyone there would have been old enough to see one purchased. That lyric is obviously not meant to be taken literally.
  • "The Doctor's Wife" by The Clockwork Quartet magnificently details an Apocalyptic Log by a doctor obsessed with curing his wife of a serious illness. The only trouble is, the dates at the beginning of each verse conform to no known calendar.
  • In the Vietnam War protest song "I Was Only 19" by Redgum is the line And Frankie kicked a mine the day that mankind kicked the moon / God help him, he was going home in June which implies that Frankie was about to go home when he was killed by a mine. But the moon landing didn't happen until July - which would mean Frankie still had almost an entire year of service to go.

    Myths & Religion 
  • The people of the northern Kingdom of Israel, who were scattered by the Assyrians and disappear from the historical record after that, are popularly known as the "Ten Lost Tribes." The only problem is that the Northern Kingdom consisted of only nine tribes — Reuben, Issachar, Zebulun, Dan, Naphtali, Gad, Asher, Ephraim, and Manasseh. The most likely explanation is that somebody subtracted the two tribes of the Southern Kingdom, Judah and Benjamin, from the traditional twelve without realizing that the tribe of Simeon had disappeared from the census at this point; and the priestly tribe of Levi (which by law had no land holdings) was spread out through both kingdoms. The math was always a bit fuzzy anyway, since Ephraim and Manasseh were actually half-tribes (being descended from Joseph's two sons) and the other tribes would sometimes kick Dan off the list for its wickedness (having slaughtered and resettled in a defenseless town in the book of Judges).
  • In the Christian Bible, a temple includes a sea (large bowl) of "cast metal, circular in shape, measuring ten cubits from rim to rim and five cubits high. It took a line of thirty cubits to measure around it," implying that pi is equal to 3 and not 3.14159. However, the sea is also mentioned as being a "handbreadth" thick. Taking the thickness of the sea into account, the numbers match quite accurately.

    Pro Wrestling 
  • Scott Steiner's infamous promo for a match against Samoa Joe and Kurt Angle in TNAnote :
    -> "You know they say all men are created equal, but you look at me and you look at Samoa Joe and you can see that statement is NOT TRUE! See, normally if you go one-on-one with another wrestler you got a fifty/fifty chance of winning. But I'm a genetic freak, and I'm not normal! So you got a 25 percent at best at beating me! And then you add Kurt Angle to the mix? You-the chances of winning drasticy go down. See, the 3-Way at Sacrifice, you got a 33 and a third chance of winning. But I! I got a 66 and two thirds chance of winning, cuz Kurt Angle KNOOOWS he can't beat me, and he's not even gonna try. So, Samoa Joe, you take your thirty three and a third chance minus my twenty five percent chance (if we was to go one on one) and you got an eight and a third chance of winning at Sacrifice. But then you take my 75 perchance-chance of winnin' (if we was to go one on one), and then add 66 and two thirds…percents, I got a 141 2/3 chance of winning at Sacrifice! Señor Joe? The numbers don't lie, and they spell disaster for you at Sacrifice!"

  • The Phantom of the Opera takes place in 1881. Its sequel, Love Never Dies, takes place ten years later, in 1907. Phantom itself has had its share of chronology issues — the dates of the prologue, the principal action, and the death of Christine's father have shifted several times since the show's inception, and trying to reconcile all three dates with each other has resulted in headaches for many a phan. A brief discussion on the subject can be found here.
  • The Pajama Game has a song named "Seven and a Half Cents" involving the singers detailing what they could buy with that raise over a given number of years. For the last figure for ten years, they forget to carry when multiplying, resulting in the wrong answer.
  • The stage version of Hairspray starts on a Monday in "early June", 1961. It ends on June 6th, 1961. However, around 10 days pass between the beginning and ending scenes. This problem is compounded by the fact that the first Monday in June, 1961, was the 4th.
  • In Fiddler on the Roof after a Time Skip, Tevye says Tzeitel and Motel have been married for two months. A scene or two later (with no time skip), they have a baby. Either Tzeitel had the world's shortest pregnancy or she somehow had no full belly when she was seven months pregnant at her wedding.
  • Charlie and the Chocolate Factory falls afoul of this in Act One with regards to Veruca Salt finding her Golden Ticket. In the "I Am" Song "When Veruca Says" her father claims that his workers were "shelling" Wonka Bars "for forty days and forty nights", but the contest was only announced the previous day. (Granted, it might have felt that way since they're dealing with Veruca Salt here.) This might be a matter of the book and the lyrics being penned by different writers.

  • BIONICLE has this across its multiple forms of media.
    • The size of the Great Spirit Robot was increased from its originally intended height (about a small-to-middle sized continent) to roughly the diameter of Earth without other measurements being changed accordingly. This means the Denmark-sized island that was supposed to be covering the fallen robot's head would't have fit.
    • Practically all forms of media disregard any given measurements when depicting the sizes and population numbers of cities or villages. Depending on which part of the story you're looking at, the population of Metru Nui/Mata Nui can be several thousands, exactly one thousand (plus its small group of leaders and protectors), or just dozens. The online games have an excuse in that they couldn't possibly have programmed that many characters.
    • Water began pouring into Karda Nui through an island-sized hole, which under a thousand years only managed to flood its bottom. While Karda Nui is a gigantic place and its sizes can only be guessed at though comparing different pieces of concept art, fans have calculated that even under the most lenient of circumstances, the place would have been filled with water in a matter of weeks.

    Visual Novels 
  • Narcissu and its sequel, Narcissu ~ Side 2nd, have trouble keeping Setsumi's age straight. In Side 2nd (which takes place during the summer of 1999), Setsumi is referred to as being an Aquaries (thus born in late January or February), and it is alternatively claimed that she is fifteen years old, or that it is her fifteenth summer (which would make her fourteen). The original game (taking place in late January and early February of 2005), claim that she is 22, but adding the years up from her claimed age in Side 2nd indicate that she should be within a month of either her 20th or 21st birthday, depending on whether one uses the "15th Summer" claim or the "15 years old" claim. Also, in the prologue of Side 2nd (which takes place between the two stories), Setsumi makes a remark about how she's been hospitalized on and off for a decade. The main story indicates that she was first hospitalized sometime in April 1997, thus making it impossible for the claim of a decade to be correct.
  • In Higurashi: When They Cry, Hinamizawa has a population of roughly 2000, yet there are only 20 pupils in the village's only school. Realistically, around one tenth of a population would be of school age. (The TIPS say that half the children in the village go to school in Okinomiya instead, which helps a little, but isn't nearly enough.)
  • Early into Super Danganronpa 2, Monokuma reveals that the students lost two years of their memories. If one however factors in all the cumulative time periods, it actually more than likely twice that number.
  • Some times in Ace Attorney don't match.
    • In the final case of Trials and Tribulations it is stated that Phoenix dated "Dollie" for 6 months, when it was actually almost 8 monthsNote . Corrected in later ports.
    • In Apollo Justice onward, most of the Phoenix Wright-era cast are a year younger than they should be, because of the botched handling of a time skip. To explain further, the trial of Shadi Enigmar happened seven years prior to the events of AJ. When calculating character ages, the writers counted from the start of T&T instead of the end of T&T. (Further confusing things, everything still takes place in the year it's supposed to - only the ages are wrong.)
  • Zero Escape trilogy deals with a lot of science and math, both basic and advanced (mostly done by Akane), and most of the time it gets it right, but few mistakes managed to slip in:
    • At one point in Nine Hours, Nine Persons, Nine Doors Seven pulls up a theory that the ship they're on is RMS Gigantic(a real-life ship that was later renamed to HMHS Britannic), to which Santa reacts with "There is no way we're on a boat that's almost 100 years old". Gigantic was finished in 1914 and game takes place in 2027, so if Gigantic still existed it would be over 100 years old.
    • Zero Time Dilemma:
      • If you fail to get the correct code in the pantry, Carlos will say that a 4 digit-code has "hundreds of thousands of possible combinations". No, it doesn't: it has exactly 10,000 combinations. Akane makes a similar mistake in the infirmary when she claims there is over a thousand possible combinations for a 3-digit code when it's exactly one thousand combinations.
      • At one point, Akane says that the probability of getting 3 ones by throwing three dice at once is 1/216 (which is correct) but attempting it three times would give 1/72 chance, which is close but not entirely correct. The probability of getting at least one success with three attempts is 1 minus the probability of failing three times in a row. In this case it's 1-(215/216)^3, or more precisely 139,321/10,077,696, which is slighly lower than 1/72.

    Web Animation 
  • Homestar Runner: In Coach Z's music video "Rap Song", a featured guest singer proclaims, "My name is Tenerence Love, plus my name is Tenerence Love, divided by my name is Tenerence Love, equals my name is Tenerence Love...remainder 3." Depending on how the operations are grouped, the value of "my name is Tenerence Love" could be -1note  or it could not exist at allnote . note  If we let "my name is Tenerence Love"=x, we have (x+x)/x=2=x+(3/x), since "remainder 3" means the undivided portion of the fraction. Rearranging, we get the statement x^2-2x+3=0, and by using the quadratic equation we find the value of "my name is Tenerence Love"=1+sqrt(2)i or 1-sqrt(2)i.note 

    Web Comics 
  • Averted in Schlock Mercenary here. The author even accounted for the equal amount of regular matter that would be converted to energy when taking 320 milligrams of anti-matter and converting to the equivalent explosion powered by TNT. (Quick link to the maths). Schlock's readers can do math as well: the writer infamously challenged them to, given a few distantly related numbers, calculate the height of the "Hellavator" lunar space elevator, only for several readers to send in accurate calculations and numbers, and show their work.
  • Angel Moxie: In-universe example. Grant accidentally fakes his birthdate as 1971, but the date of his teaching degree as 1983. Luckily, the only ones who notice are the heroines.

    Web Original 
  • The Creepypasta story The Russian Sleep Experiment starts out with five Nazi prisoners and has three by the time they leave the facility, yet still manages to include death scenes for four or five after that.

    Web Videos 
  • The Nostalgia Critic, in his End of Days review, as part of a long string of math equations, infamously uttered that "9+9+9=21". That's about as basic of mathematics as one can get and he screwed it up. He later apologized for it in one of his "Fuck ups" specials.
  • Mario Party TV: One comment pointed out that Steeler miscalculated the odds during the Pagoda Peak playthrough. The probability of rolling 4 of the same number is not 1/10,000. Since the dice blocks are numbered one to five, and there are 5 possible ways to get all 4 numbers being the same, the probability ends up being: 5/(5^4) = 1/125 (about the same as a golden with 1-10 blocks)

"80% of you have no understanding of percentages!"
"We aren't even that many..."

Alternative Title(s): Writers Cannot Do Maths, You Fail Mathematics Forever