How many ways can you arrange a deck of cards? Yannay Khaikin explains the mind-boggling math.
Enjoy!
One deck. Fifty-two cards. How many arrangements? Let’s put it this way: Any time you pick up a well shuffled deck, you are almost certainly holding an arrangement of cards that has never before existed and might not exist again. Yannay Khaikin explains how factorials allow us to pinpoint the exact (very large) number of permutations in a standard deck of cards.
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According to a news report, a certain private school in Washington recently was faced with a unique problem. A number of 12-year-old girls were beginning to use lipstick and would put it on in the bathroom.
That was fine, but after they put on their lipstick they would press their lips to the mirror leaving dozens of little lip prints. Every night, the maintenance man would remove them and the next day, the girls would put them back. Finally the principal decided that something had to be done. She called all the girls to the bathroom and met them there with the maintenance man. She explained that all these lip prints were causing a major problem for the custodian who had to clean the mirrors every night. To demonstrate how difficult it had been to clean the mirrors, she asked the maintenance man to show the girls how much effort was required. He took out a long-handled squeegee, dipped it in the toilet, and cleaned the mirror with it. Since then, there have been no lip prints on the mirror. There are teachers, and then there are educators… |
Is there actually a couch-potato gene? Obama admits he has it. Sarah Palin can even see it from Alaska.
Why are some people so lazy? Is there a couch-potato gene?
How to make gunpowder and what you need.
Gunpowder, also called black powder, is a simple mixture of saltpeter, sulfur, and charcoal. The trickiest part of making black powder is sourcing these three supplies. Once you find them, you mix them together and create an explosive black meal. Be extremely cautious when handling black powder, and make sure to store it away from heat and flame.
Get your hands on some saltpeter. Saltpeter is the common name for potassium nitrate. In the days when black powder was widely used, saltpeter was manufactured from bat guano or made from horse urine and other “manurial soils.”[1] It’s used in many fertilizers, as part of science projects, and in certain recipes. You have several options for sourcing saltpeter:
- Look for “stump remover” in garden stores. Saltpeter is often sold under this name. You may also find it labeled as saltpeter, niter, or potassium nitrate.
- Buy it online. If you do a search for saltpeter, you’ll get plenty of results, and you can easily have a bottle delivered to you.
- Make it yourself out of a cold pack. Cold packs you can buy for a few dollars to help with sore muscles contain sodium nitrate and water, and can be used to make saltpeter.
- Make it with urine. This is definitely the most difficult way to source saltpeter, but some black powder enthusiasts prefer to make their powder entirely from scratch. To do so, one process is to fill a drum with manure affixed with a drain, valve, and filter at the bottom. Urinate into it, then top it off with water. After about 10 months, dry it out on trays.
Thanks to Today I Found Out, we find out were the words “geek” and “nerd” came from.
The first documented case of “geek” dates all the way back to 1916. At the time, the term was used to describe sideshow freaks in circuses. Specifically, it was typically attributed to those circus performers who were known for doing crazy things like biting the heads of various small live animals or eating live insects and the like. These performances were often called “geek shows”. The word itself, “geek”, came from the word “geck”, which was originally a Low German word which meant someone who is a “fool/freak/simpleton”.
The first documented case of “nerd” was in Dr. Seuss’s If I Ran the Zoo, in 1950. The specific text was: “a Nerkle, a Nerd, and a Seersucker too”. It was just one year after the Dr. Seuss book, in 1951 in a Newsweek magazine article, that we find the first documented case of “nerd” being used similarly to how we use it today. Specifically, they used it as being synonymous with someone who was a “drip” or a “square”.
There are two popular theories as to where the word derived from. The first is that it was perhaps derived from “drunk” spelled backwards, “knurd”. This was fitting to describe people who studied instead of going out with friends and partying. A somewhat more popular theory suggests that it came from a modification of “nut”, specifically “nert”, which meant “stupid or crazy person” and was common in the 1940s, directly before the term “nerd” showed up. The word nerd ended up becoming fairly popular in the 1960s and by the 1970s was hugely popularized by the TV show Happy Days, where it was used frequently.