Welcome to Add It Up, our new math blog for parents and educators! Having shared an exciting year of kid-appealing math for parents and their children, we’re expanding our horizons. As much as parents enjoy adding up octopus legs and doughnut holes, we realize you all might want something a little more grown-up for yourselves.
Today is the 10th birthday of iTunes, the online store that lets you buy songs, movies, apps for your smartphone, videos…all kinds of stuff that you can enjoy on your phone or computer. Before iTunes, the only way we old-timers could buy songs was on something you could hold in your hand, like a CD, a tape cassette or a vinyl record. Or you could get songs electronically from various illegal websites, which was exciting but felt icky. So the idea that you could get onto your computer, buy any song you wanted (legally), and get it within seconds was mindblowing. iTunes opened with just 200,000 songs on it, all priced at 99 cents, and within just one week they had 1 million song downloads. As of today, iTunes has sold over 15 billion song downloads from a collection of 26 million different songs. Let’s just say, it takes far more than one person to listen to it all.
On this day in 1876, Alexander Graham Bell finally got his invention working: the telephone. It worked nothing like our phones today: the very first phones were sold in pairs, where each phone could call only that one other phone (you had to pick that other person carefully). Then came the “switchboard,” which let you call any other phone, but the “operator,” a phone company person in the middle of town, had to plug in wires to connect your call for you. Now we can call anyone anywhere on our own within seconds, and through the air. But that first phone, that first time talking to someone through a wire, must have looked like magic.
You’ve probably heard of biking to work, but biking at work is a whole other story. A recently invented work desk, called the WeBike, makes people work for their, well, work. As you sit at your desk, you pedal the bike, which generates the electricity to power your laptop, printers, phones, and other electronics. It seems like kids could use this thing even more than adults, to power all the batteries you need for your toys. And imagine if you had these bikes at school…could it do your homework for you?
Until pretty recently, when you wanted to find your way somewhere, you had to pull out a paper map, face it the right way, figure out where you were on the map, and then figure out how to get to your destination. Now we’ve taken all the fun out of it. With the digital maps on our smartphone and computer screens, you just type in your start and end points, and it draws the path you should take. Then geopositioning systems, or GPS, use satellites to find you and plop a blinking dot on the screen to show you exactly where you are. Now when taking a trip by car, thanks to GPS the days of crumpled maps are over. But as we’ll see here, when it comes to timing, sometimes the system doesn’t know everything.
When it snows outside and you get that really wet, sticky kind of snow, it’s easy to pack it with your hands into a solid white ball that just begs to be thrown. Sure, you can roll it along the ground to make it bigger, and pile up a few to make a snowman…but it might be even more fun just to chuck it at someone. We’re not exactly sure who invented the snowball fight, but we do know that in 1863, during the American Civil War, when a few soldiers started chucking friendly snowballs at each other, it turned into a giant fight involving 9,000 soldiers. If serious grownups can get sucked in like that, it’s clear the snowball fight is here to stay.
One of the most popular and widespread toys ever invented is the Rubik’s Cube. The mission is so simple: just turn the rows and columns to swap around the pieces and get all six faces to be solid colors. And yet that turns out to be one of the hardest challenges out there – maybe because a 3x3x3 cube has over 43 quintillion possible line-ups of the pieces. Ever since the cube was invented in 1974, over 350 million of these puzzles have been sold; the Cube has inspired people to set all kinds of records, spawning speed cubers, one-handed cubers, and the real geniuses who study the cube, blindfold themselves and solve it from memory. To get a taste of the excitement, let’s look at the math behind cracking the code.
The last week of January often marks the coldest week of the year, at least for the northern half of our planet. We’ve been tilted away from the sun for weeks, we’ve had short days of sunlight, and in some places cloudy gray skies make matters worse. So it’s no surprise that many states have had their coldest temperature ever in late January or early February. When you see some of the records set over the decades, you might find that a bowl of ice cream at 3 degrees F could warm you up.
It’s pretty exciting to get on a roller coaster, tip over the top of a hill and plunge toward the ground at 30 miles an hour. But it’s even more alarming to do this in the dark. On this day in 1975, Disney Parks opened Space Mountain, the famous roller coaster at Disney World in Orlando, FL. The entire ride spirals around the inside of the mountain, dark except for sparkly stars and some pulsing lights, which do nothing to help you see where you’re going. So every twist, turn and plunge comes as a total surprise. Clearly lots of daredevils love this kind of thrill: over the decades hundreds of thousands of visitors have ridden Space Mountain, leading Disney to build four more of them around the world.
On this day in 1930, a certain cartoon character showed up in U.S. newspapers for the first time: Mickey Mouse. When Walt Disney and Ub Iwerks first drew this friendly rodent two years earlier, he probably had no idea that a mouse could become so popular. With his high voice, red shorts, and poofy yellow shoes that look impossible to walk in, Mickey is one of the world’s most famous cartoon characters. He was also the first cartoon character to get a star on the Hollywood Walk of Fame alongside real humans – after all, he wears clothes, too.