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# Anti-Pi Rant, 3/14/14

Sorry, Pi lovers! Maybe pick a better favorite number next time? Created by Vi Hart.

## Want to join the conversation?

• At she said: "If you threw a dart and picked a random number of the number line, the chance of getting a rational number is exactly 0"
My question is simple; Why? • If you have a set of anything.... say a deck of 52 cards, the odds of picking any one card form that deck is 1 in 52. If the deck has infinite cards, then the odds of picking that same card is then 1 out of infinity. 1 divided by infinity is zero. That is what she means. Picking any non-rational number out of a set of infinity can be any finite large number divided by infinity. BIG INSANE EPICALLY LARGE NUMBER divided by infinity is still .... zero. So she's right!
• pi can be written, when in fraction form, as 22/7, so doesn't that technically make it rational? Or is this fraction just an approximation of the real value of pi? • It is an approximation. It is one of the more famous ones because when Archimedes calculated pi, he put inner and outer bounds on a circle with polygons, and that was one of his less accurate approximations. It is greater than pi because it is approximately equal to: 3.14285714286. A better approximation would be 355/113 which is good to 6 decimal places. The only ones better than that have denominators greater than 30,000.
• why do we HAVE pi day. i mean pi is cool (like tau), but why do we have a holiday for it? • Why do we have the Grand Holiday of Pi Day? Good question. As Vi says in "Pi is (still) wrong," the reason schools teach you all the equations with Pi instead of Tau and Christopher Columbus discovered America (which he didn't) and make Columbus Day a Grand Holiday -- the reason is because that's what people have been doing for a very long time, and people naturally don't like change. They like order and routine. If somebody started celebrating Pi Day, other people, not knowing about Tau, would say, "Pi Day? That sounds cool!" So now Pi Day is a Grand Holiday. If people all of a sudden started celebrating Tau Day, in fifty years it would be a Grand Holiday, too. So to answer your question, we Columbus Day and Pi Day and Washington's Birthday and Lincoln's Birthday and President's Day and Talk Like a Pirate Day is because that is what people have done for a very long time, and they don't want to change it. Speaking of which, you could make E Day into a Grand Holiday. E or Euler's Number is another irrational, approximately 2.718281828459 . . .
Godspeed!
--Blue Leaf
• At 2 minutes and around 44 seconds, why is it you say that if you throw a dart on the number line there is a zero percent chance of getting a rational number? The definition of rational is if a number can be written as a fraction, or a decimal that terminates or repeats. There are gazillions of numbers that can be rational, and throwing a dart on a number line can bring you to one of those numbers. Another question. The whole point of the video was to understand that pi is not infinite, yet there are infinite numbers to pi as you claimed at 1 minute and around five seconds. If there are infinite NUMBERS, then why is pi not infinite?. Pi is a number after all. • There are an infinite number of rational numbers, but there are even more irrational numbers. We can actually count the number of rational numbers, but the number of irrational numbers are uncountable and so infinitely more common. As a result, the chance of choosing a rational number out of all real numbers is zero.

There are an infinite number of DIGITS to pi, but pi is still not infinite. Every number in existence has an infinite number of digits. Does that make every number in the world infinite? Either way, pi is nothing special to be venerated.
• • Pi is a number that is three and a bit. That isn't very big. The digits of pi go on infinitely but that is not really pi itself, just a load of decimal digits that help to approximate it. Draw a line. Draw a semicircle on that line. That semicircle is pi relative to the radius you used, of course. That is more fundamentally pi than any sequence of digits. Doesn't look very infinite does it? You didn't even use up the whole pencil. ;-) So there are infinite things about pi, but no more so than any other irrational number or maybe even any other number. This stuff is not what makes pi special, That semicircle you drew (or imagined) is what makes pi special.
• I don't get how the chances of throwing a dart on a number line and getting a rational number is 0. There has to be some chance. For example, 5 is rational so there is a tiny chance that you will get a rational number.  • • • 