That, when performing calculations for interplanetary navigation, NASA scientists only use Pi to the 15th decimal point. When calculating the circumference of a 25 billion mile wide circle, for instance, the calculation would only be off by 1.5 inches. jpl.nasa.gov/edu/news/201…
In 1790, Thomas Jefferson proposed a decimal-based system for weight, length, and volume that predates the metric system. If it had been adopted, 1 mile would equal 10,000 ft, an inch would be divisible by 10, and 1 cubic foot would equal exactly 1,000 ounces. en.wikipedia.org/wiki/Pla…
There is a sequence of six 9's which occurs in the decimal representation of the number π starting at the 762nd decimal place. This mathematical coincidence is also known as Feynman point. en.wikipedia.org/wiki/Six…
Today I learned of a 3800 year old estimate of the Square Root of 2, from Babylon. It is accurate to 6 decimals or 1/2,000,000, the greatest in the ancient world. This indicates that it was computed iteratively, instead of being a mere estimate. Numerically it's: 1 + 24/60 + 51/60^2 + 10/60^3. en.wikipedia.org/wiki/YBC…
The largest decimal unit prefix in the metric system is yotta (10^24) and the smallest one is yocto (10^-24) chem.libretexts.org/Books…
Spain's newest submarine was 75+ tons heavier than expected because someone put a decimal point in the wrong place. It could go down, but might not come up again. popularmechanics.com/mili…
Spain’s S-80 submarine program designed subs that were 70 tonnes too heavy, and likely sink when submerged. Cost overruns to fix it are expected to reach \$9 billion. The problem was traced back to an engineer misplacing a decimal point, and had been called the most expensive math error ever. o.canada.com/news/spain-b…
Swatch Internet Time was a decimal time concept introduced in 1998 by the Swatch corporation. Instead of having time zones, hours, and minutes, decimals were used to measure what time it was. en.wikipedia.org/wiki/Swa…
The french numbers is a blend of the decimal system of cont, used in Roma, and the vigesimal system of count, used by the Celtics, and it became official only in the century 17 elsafrenchteacher.com/why…
It wasn't until 15 February 1971 (Decimal Day) that the UK decimalised its currency. Before this date in the UK, each pound was made up of 20 shillings, each shiling was made up of 12 pence, which meant each pound was 240 pence. en.wikipedia.org/wiki/Dec…
On the Kate Bush track π (Pi), she sings the digits of pi, but gets the 54th decimal place wrong, and later skips 22 decimal places, for reasons which remain unclear. genius.com/Kate-bush-pi-l…
Decimal Separators like , and . are used differently by region en.wikipedia.org/wiki/Fil…
Srinivasa Ramanujan. (Happy Birthday! 22 Dec 1887-26 Apr 1920) discovered wonderful formulae for calculating pi. "Thanks to the theoretical foundations that Ramanujan laid ... powerful computers have calculated the first 10 trillion decimals of the number pi." 22nd Dec is also India's Math Day bbvaopenmind.com/en/scien…
Al-Khwarizmi from Baghdad around A.D. 800 worked on a value of pi calculated to four decimal digits: 3.1416. The term 'algorithm' derives from his name, and his text Kitab al-Jabr wal-Muqabala gives us the word 'algebra' (from al-Jabr, which means 'completion' or 'restoration') en.wikipedia.org/wiki/Muh…
There is a community called the "Dozenalists" that believe a base-12 counting system, instead of our current base-10 (decimal) system, is a more efficient way of conceptualizing and understanding mathematics. io9.gizmodo.com/5977095/w…
Melvil Dewey, the inventor of the Dewey Decimal System, was kicked out of the American Library Association for constant unwelcome advances towards women librarians. americanlibrariesmagazine…
Writer and biochemistry professor Isaac Asimov is published in 9 of the 10 categories in the Dewey Decimal System en.wikipedia.org/wiki/Isa…
The world record for most Pi places memorized is held by Rajveer Meena who recalled 70,000 decimal places. guinnessworldrecords.com/…
Until decimalisation on Decimal Day in 1971, one pound was worth 240 pence. After Decimal Day 1 pound was worth 100 new pence which became just pence in 1981. en.wikipedia.org/wiki/Pou…
Today I learned of illegal numbers. Since binary information representing illegal things (from DVD rippers to CP) can be written in regular decimal, US law considers possession or distribution of these numbers as illegal. en.wikipedia.org/wiki/Ill…
, the physical size and value of the US Dime (1⁄10th of a sliver dollar) was first proposed by Alexander Hamilton, and other founding fathers, who advocated for a decimal-based coinage system. en.wikipedia.org/wiki/Dim…
A UK university was fine £400,000 after 2 students were accidentally given a lethal dose of caffeine during a scientific experiment. Because of a misplaced decimal point on the phone used to calculate the caffeine dosage, they received 30g instead of the planned 0.3g. The lethal dose is 18g. rt.com/viral/375088-letha…
Today I learned about Decimal Time, used in France in 1792 during the French Revolution, which divided the day into 10 decimal hours, each decimal hour into 100 decimal minutes and each decimal minute into 100 decimal seconds. Basically metric time. en.wikipedia.org/wiki/Dec…
It has never been proven that the decimal expansion of pi contains every possible finite sequence of digits, although mathematicians believe it is probably the case, and it the subject of some mystic memes which assert this to be true. huffingtonpost.com/david-…
Engineers used to rely on imprecise calculations with slide rules that only showed three decimal points but designed the Empire State Building, Saturn V rocket with them. As a result, they designed conservatively by making walls thicker and bridges stronger than needed uvm.edu/pdodds/files/pape…
Some countries use a decimal point instead of commas for numbers above a thousand. Ex. 100.000 ( 100,000 ) en.wikipedia.org/wiki/Dec…
The reason Popeye eats spinach is because of an error in the calculation of its iron content by chemist Erich von Wolf in 1870. He misplaced a decimal point, recording iron as having 35mg of iron per 100g, instead of its true value of 3.5mg/100g. The former is equal to eating part of a paperclip brainpickings.org/2013/07…
Today I learned of "Decimal Time," a unit of time that divides the day into 10 hours, an hour into 100 minutes, and a minute into 100 seconds. en.wikipedia.org/wiki/Dec…
France Once Tried Simplifying Time By Using A Decimal Clock, In Which There Are Only 10 Hours In A Day mentalfloss.com/article/3…
In Star Trek: The Original Series, The writers were told to pick four random numbers to use for the Stardate, and apply a decimal point for time of day, such as .5 for noon. This was done to preserve the shows futuristic feel, and to not relate it to our unit of time. mentalfloss.com/article/6…
The reason Popeye eats spinach is because of an error in the calculation of its iron content by chemist Erich von Wolf in 1870. He misplaced a decimal point, recording iron as having 35mg of iron per 100g, instead of its true value of 3.5mg/100g. The former is equal to eating part of a paperclip brainpickings.org/2013/07…
The French Revolutionists were not the first to attempt to use decimal units of time (each day divided into units of 10). The Chinese were using it by the 1st millenium, BC. en.wikipedia.org/wiki/Dec…
Before 1971 penny referred to a coin 1/240th the value of a pound. 15 February 1971, known as Decimal Day, the day United Kingdom and Ireland decimalised their currencies. Before Decimal Day in 1971 twelve pence made a shilling, and twenty shillings made a pound, hence 240 pence in one pound. en.wikipedia.org/wiki/Dec…
Isaac Asimov wrote over 500 books, spanning nine out of the ten Dewey Decimal classes en.wikipedia.org/wiki/Isa…
The French proposed the use of 'Decimal' time, with 10 hours in a day, and 100 minutes in an hour, etc. en.wikipedia.org/wiki/Dec…
Today I learned of Gunter's Chain - a measurement device invented in 1620 which reconciled the Imperial and decimal systems. The 66 foot long chain is also the basis for the modern length of a cricket pitch. en.wikipedia.org/wiki/Gun…
The only two countries that use a non-decimal currency are Mauritania and Madagascar. en.wikipedia.org/wiki/Non…
Mathematician William Shanks' lifetime of work led to the determination of the value of Pi to 707 decimal places in the year 1873. 75 years later, calculations on a desk calculator revealed that the last 180 decimal places were incorrect. mathlair.allfunandgames.c…
While most countries place the currency symbol either before or after the amount, the Cape Verdean escudo places its symbol in the decimal position (i.e 20\$00) en.wikipedia.org/wiki/Cur…
At the age of 17, Srinivasa Ramanujan had developed Bernoulli numbers and calculated Euler’s constant up to 15 decimal places nytimes.com/1987/07/14/sc…
Isaac Asimov wrote or edited more than 500 books and an estimated 90,000 letters and postcards. His books have been published in 9 of 10 major categories of the Dewey Decimal Classification. He is the 17th most-translated author, just behind Arthur Conan Doyle and ahead of Pope John Paul II en.wikipedia.org/wiki/Isa…
The Dewey Decimal Classification is a proprietary system as a subscription is needed to access notes on constructing call numbers. en.wikipedia.org/wiki/Dew…
Russia was the first country to introduce decimal currency in 1704 en.wikipedia.org/wiki/Dec…
More countries use a comma than a dot as a decimal point. (e.g. 0,01 rather than 0.01) en.wikipedia.org/wiki/Dec…
Using an approximation of Pi to 39 decimals is accurate enough to calculate the circumference of the universe to within one atom. en.wikipedia.org/wiki/Pi#…
There's a difference in writing repeating decimals between countries - when in Germany you would write a line over the repeated digit you would write a dot over it in Austria en.wikipedia.org/wiki/Rep…
There is a simple integral expression that evaluates almost exactly to pi/8 -- the values agree to 42 decimal places -- even though it's just a wild coincidence and pi/8 has nothing to do with the true value. en.wikipedia.org/wiki/Mat…
The meter was redefined in terms of the speed of light in 1983, and so the speed of light is now precisely and by definition 299,792,458 m/s. No decimals. nist.gov/pml/div683/uploa…
France, for a few years beginning in 1792, switched to Decimal Time. There were 10 hours a day, 100 minutes per hour, and 100 seconds per minute. en.wikipedia.org/wiki/Dec…
After the French Revolution, France used a simplified decimal time and calendar system for 13 years which had 10 hours a day, 100 minutes per hour, and 100 seconds per minute. www-history.mcs.st-and.ac…