How many Rubik's Cube combinations are there?

...Well, lets start off easier and ask how many ways you can put the stickers on. If you number the stickers of each color 1-9, so that all 54 stickers are unique, there are about 231 duovigintillion ways to put them on the cube. That's 231 followed by a whopping 69 zeros. Let's get more complicated and ask how many ways you can arrange the pieces on it (now without numbering them). There are 8 corner pieces that can each be turned in 3 ways while in one spot, 12 edge pieces that can each be turned in 2 ways, and there are the center pieces that never change position. With that, there are about 519 quintillion (519 followed by 18 zeros) ways you can arrange the pieces on the cube. In order to get the real answer for the number of combinations on a Rubik's Cube, you have to take into account the fact that you can't get to every arrangement just by twisting the cube. I don't quite understand the math for this part, but Numberphile has made a video about it, revealing that there are exactly 43,252,003,274,489,856,000 Rubik's Cube combinations, or about 43 quintillion.

Here's a few Rubik's Cube videos made by Numberphile:

http://www.youtube.com/watch?v=QV9k6dRQQe4&list=PLt5AfwLFPxWJNAdHv8TUCOmj7iKqyHZeg

How long would it take to figure out you iPhone pass code lock?

...Well, the most time it could possibly take to guess someone's pass code would be just over 5 1/2 hours, and that's if it took half a second to press each number and you tried every single possible combination and did it nonstop. Let's also ignore the fact that an iOS device locks you out if you get the pass code wrong too many times. Not to mention you're probably going to mess up at some point with 10,000 combinations. The way you would do it would be to start with 0000, then 0001, then 0002, and so on until you reach 9999. But then a lot of people will have repeating numbers for their pass codes like 9999, so it would be a good idea to try those first, not that you should actually try to break into someone's iPhone. See you next time, and don't spend 5 1/2 hours trying to break into someone's iPhone! It's not worth it!

P.S. If you saw when I had this post up before, I was completely oblivious to the fact that there was actually a 0 on the pass code keypad. All good now!

Science on the internet

There are several YouTube channels that are great for people who enjoy science and math, and even for people who don't. You can visit and subscribe to Veritasium, Minute Physics, Minute Earth, Smarter Every Day, Vsauce, Vihart, and Numberphile. You can view a page about them here. And here is a video by minutephysics about more science on the internet. Please check them out!

http://www.youtube.com/watch?v=i8t53Ak_yrQ

What is 0/0?

Because of school, I probably won't be able to post news during the week, so every now and then I might just post a short math fact, like this one. Most people when asked what is 0 divided by 0, would say 0 without hesitation. They even teach that in school, and I went several years thinking that until recently, but is that really right? Well, it's partly right. 1 infinitieth right to be exact. It turns out 0/0 equals anything you want. If you think about it, dividing is just figuring out how many times you have to multiply something to get a number. Since 0 * 0 = 0, and 0 * 1 = 0, and 0 * 1,000,000,000,000,000,000,000,000 = 0, these are all logical answers. Here's another way to prove it. If you graph a line with the equation y = x, the y divided by the x is always 1 at any point, so why should it be any different for (0, 0)? In fact, the y/x (or vice versa) is always constant for any line graph that passes through the origin, so the most logical answer for y/x at (0, 0) is whatever it is at the other points. So there you have it. 0/0 = any possible number you can think of.

Answer!

          Without all the math, here are the answers to gold questions. All the gold in the world would weigh 361,920,936 pounds. It doesn't sound as small that way, does it? (If you remember that it would fit in a cube with sides 67ft long) That would all cost over $8 trillion! Or $8,190,542,222,382 to be exact. Before the next answer, I want to point out that I messed up on the amount of storage space in a truck, which was really 4,006.4 cubic feet. It would almost fit in 75 trailer trucks, so it would take 76 to carry all the gold. You could make 1,565,992 solid gold bowling balls, each weighing 231 pounds. That's a bit heavy for bowling. Finally if you got about 348,000 of the world's strongest men, they might just be able to lift all the gold in the world.

All the gold in the world could fit into a cube with sides 67ft/20m long

          I couldn't think of a shorter title, so there you have it. I found that BBC News does this thing called 10 things we didn't know last week that is a list of 10 newly discovered facts. The 9th fact about gold (above the ground) just happened to be featured on a twitter post and it had a lot of math potential. We can answer questions like: How much does all the gold in the world cost? How much does it weigh? How many 53ft trailer trucks would it take to carry it using the maximum amount of space? How many solid gold bowling balls could you make? How heavy would each bowling ball be? How many Olympic weight lifting gold medalists would it take to lift it? How many more questions can you think of? If anyone actually wants to do any of these, here's some info: 1 pound of gold is 1.436 cubic inches. A pound of gold costs about $22,630.75 today, but it changes daily. A 53ft trailer truck has 4,006.4 cubic feet of storage space. A bowling ball is about 331.878 cubic inches. And finally, the Olympic record for weightlifting is 472kg which is 1040.288lb. Check back soon for the answer!

Answer!

          I Have no news for you today, but here's the answer to yesterday's post. Since there's no way of knowing exactly how the President gets paid, we can only assume that he gets $33,333.33 a month (He would only lose 4 cents a year). He will get paid 47 times starting from the beginning of this March to the end of January 2017. With his full salary, he would get $1,566,666.51. Five percent of that is exactly 78,333.3255, and because we're dealing with money, it's unsure whether it would be rounded up or down, but let's just stick to the rules and round it up to $78,333.33. It seems like quite a lot of money, but that's only 0.000000466% of the national debt! In other words, it's just about 1/214,592,275.

Obama gives back 5% of his income

          The title speaks for itself, but before that, here's yesterday's answer. (I recently added in China's population in last post, as I forgot to include it before. I also made the mistake of using current populations instead of 2010 populations, but that shouldn't change the answers too much.) First, if you do 1,200,000 (deaths from air pollution in China) divided by 1,354,000,000 (China's population) you get 0.08863% of the population dead from air pollution, which also the probability. There were 2,000,000 deaths in the rest of the world (That's 3,200,000 total), and the population in the rest of the world is 5,722,000,000, so the average probability of dying of air pollution in 2010 in the world excluding China was 0.03495%. That means you had a 0.05368% higher chance of dying in China from air pollution. That's more than double the chances, and fairly close to triple!

          On March 1st, President Obama started giving back 5% of his $400,000 a year salary to the government to contribute his sacrifice to the sequester. Little does he know, though, that he gave me a great topic for my blog. I can show you just how much in debt the government is, which is a mind boggling $16.8 trillion. Assuming Obama gives this money for the rest of his presidency, if his term ends starting at noon on January 20th and gets paid monthly, how much money is he losing and what percent of the national debt is that? One more thing is that I don't know what day of the month the president gets paid, but it doesn't change the answer as long as it's not after the 20th of every month (or at least January). So let's assume that he get's paid before the 20th. Check back tomorrow for the answer!
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1.2 million died in China from air pollution in 2010

          A new study shows that about 1.2 million people died in China as a result of exposure to air pollution in 2010, but first let's see the answer to yesterday's math question. If we do a simple 0.11 * 76,700,000, we get 8,437,000 children currently in the US with ADHD. But we can be a little more accurate by estimating the number of kids from 4-17 years old, because the 76.7 million was the number of children from 0-17. Since 0 counts as an age, we want to take out 4/18 of 76.7 million to get about 59,655,556 children from age 4-17. Now, if we do 11% of 59,655,556, we get about 6,562,111 total children in the US diagnosed with ADHD. I also found a web page from last year that said that 5.2 million children of age 3-17 are diagnosed with ADHD, which, according to the article, is 8.4%, so our answer should be pretty close.

          Now, about that air pollution thing. As I said, there was a new study showing that 1.2 million people died in China, and 3.2 million total around the world as a result of air pollution in 2010. Knowing that there are about 7.076 billion (7,076,000,000) people in the world, and 1.354 billion people in China, what were your chances of dying from air pollution in China compared to your average chance of dying from it in the rest of the world? Find out tomorrow!
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Google April Fools!

This has nothing to do with math, but today Google announced their Google Nose. If you go to the Google website, their's a link below the search box that takes you to a page about it. Find out for yourself here.

(For some reason the videos don't work on mobile devices)

YouTube also put up a video yesterday saying that it would shut down at midnight and select a winner for the best video.

Happy April Fools!

11 percent of kids have ADHD

Welcome to my first Math in the News post! It has been reported that 11 percent of children of age 4-17 are diagnosed with ADHD. There are 76.7 million children in the US (That's from 0-17, so it's not exact), so how many have ADHD? Find out in the post tomorrow!
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Math in the News

          Greetings! This will probably the last time I say greetings. I'm going to start a new thing called Math in the News on the homepage, where I post news stuff with numbers that will hopefully have cool properties I can find, or just math stuff directly related to the news. See you next time!