Funbers 19, 20 and 21
The fun facts about numbers that you didn’t realise you’ve secretly always wanted to know…
19 — NINETEEN
Nineteen holds a significance for most people alive today as the first two numbers of the year in which they were born (sorry millennials). The 1900’s were also big in terms of technology; we started with aeroplanes in 1903, bras in 1913, televisions in 1925, canned beer in 1935, microwave ovens in 1946, CDs in 1965 and finally Viagra in 1998. I’ll leave you to decide which are the most important…
Nineteen also has some bad blood — there are 19 angels guarding hell in the Qur’an and the ‘Nineteen Propositions’ were pretty much the cause of the English Civil war of 1642. As the name suggests, they were a list of nineteen demands that would change the manner of the English government and effectively transfer power from the Royal Family to parliament. Needless to say, the King at the time, Charles I, was not on board with this idea and war shortly followed. The Parliamentarians were eventually victorious led by the infamous military commander Oliver Cromwell (there’s a statue of him in my hometown of Warrington — no idea why, but here’s me climbing on it).
20 — TWENTY
The number of children fathered by the German composer Johann Sebastian Bach, a sign that you have perfect eyesight and the number of championship titles won by Manchester United — the number twenty tends to be associated with good things… well apart from the roaring 20’s which were a time of both boom AND bust. Following the First World War everyone was keen to get things back on track, leading to the first transatlantic flight, the mass-produced car and the wonder drug of penicillin. Fun was also to be had with the creation of Jazz and an incredibly long list of entertainers that included Charlie Chaplin, Ernest Hemingway and Harry Houdini to name but a few. Unfortunately, the bust came in 1929 with the Wall Street Crash and the start of the Great Depression.
Twenty also happens to be the number of choice for the counting system of the Mayans. They work in what we call base 20 — with a line representing 5 units and a dot 1 unit. When you reach 20 in the current row, you put a dot in the row above, much in the same way that we add a 1 to the column to the left once we reach 9 in the previous column. For example, a single dot with another single dot below and finally three dots and two lines on the bottom gives (3 x 1) + (2 x 5) + (1 x 20) + (1 x 400) = 433 (see figure below). The first lot of twenty comes from the single dot in the 2nd row and the 400 comes from the single dot in the 3rd row, which means that we have one lot of 202 = 20 x 20 = 400. Our numbers in base 10 are very similar with the second column to the left telling us how many lots of 10 and the third column to the left how many lots of 102 = 10 x 10 = 100.
21 — TWENTY-ONE
Twenty-one is traditionally seen as the age of adulthood in many countries across the world, though no-one really knows why… Theories range from the mathematical — it’s the product of two lucky numbers 3 and 7; to the medical — for many centuries it would be seen as middle age or at least the age beyond which you are deemed to have had a good innings. If you have any theories of your own be sure to let me know!
21 is also the number of shots fired in a peaceful gun salute to signify no hostility or to honour royalty and heads of state. The reason for the 21 shots is to empty your gun sufficiently that it would take a long time to reload and be ready to fight. Whilst this may have had some use back in the day, with the invention of rapid-fire automatic weapons it would be fair to say that it doesn’t quite cut the mustard anymore…
Finally, let’s end with some fun and games (emphasis on the latter). Twenty-one is a big number in the world of gambling; from Black Jack, where the aim is to draw cards with a total as close to twenty-one as possible, to the number of dots on a die — craps anyone? And of course, who could forget the drinking game. I’ll start: to my left 1,2…
Author
The Funbers series is written and presented by Dr Tom Crawford and is broadcast weekly on BBC radio. For more maths fun check out Tom’s website tomrocksmaths.com and follow him on Twitter, Facebook, Instagram and YouTube @tomrocksmaths.
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