A lot of kids don’t enjoy math in school. Numbers can be a little dry and sometimes that doesn’t translate into keeping people interested or entertained. But sometimes mathematical equations and statistics can be spun in ways that are completely mind-blowing. You just have to know what to look for. Like these calculations, for instance.

## 10. The Hoover Dam Would Have Still been Cooling Down Today If It Was A Single Concrete Pour

The Hoover Dam was one of the most massive Construction undertakings in US history back when it was created in the 1930s. The base of the dam is wider than two football fields. There’s a stunning 3.25 million cubic yards of concrete in the dam alone, not including what power plant and surrounding structures. They were sometimes using over 10,000 barrels of concrete per day in its construction.

Part of the building process involved producing individual trapezoidal columns of concrete to put it all together. This is because the math behind doing it all in a single pour was not working for them. Because the process of concrete drying and setting produces heat, it was calculated that it would take 125 years for the concrete to cool if it had been poured all at once. Meaning it would still be cooling down right now.

A side effect of the extended cooling process would have been severe structural weakness. The dam would have broken apart long ago.

## 9. Indonesia Calculated That a Single Manta Ray is Worth $1 Million Tourist Dollars

Tourism is a strange industry when you stop to think about it. You can always calculate how much tourists spend in your city or country in a year and get a basic understanding. But what about stepping back and looking at it from the point of view of what is attracting tourists in the first place. What is it you have, as a tourist destination, that draws people in? And, in turn, what is the value of that thing?

For instance, you could say many people go to New York to see the Statue of Liberty. So how much is the Statue of Liberty worth, in dollars, to New York City? You can leave that up to City Hall to figure out, but over in Indonesia they have realized that one of their big tourist draws are the manta rays that live in the ocean around the country. And rather than just resting on their laurels by acknowledging these fish are money makers, someone sat down and calculated just how much they add to the local economy.

Because tourists will pay money to swim with manta rays, a manta ray conservation site was set up. It’s been calculated that, over the course of its lifetime, each manta ray in Indonesia is worth one million tourist dollars. Compare that to the value of one hunted for food which is only $500 at most but can be as low as $40. Every year about $15 million is made off of manta ray tourism alone.

## 8. NASA Can Calculate a 25 Billion Mile Sphere to 1.5 Inches With Just 15 Digits of Pi

Pi Is the ratio of the circumference of a circle to its diameter. Most of us know it as 3.14 which is a tiny portion of the true number which is, as far as we know, an infinite number. More on that in a moment.

In mathematics, pi is essential for calculating things like arcs, ellipses, any curved dimensions, really. On a grand scale, you can use it to calculate something like the size of the entire universe, so that’s pretty cool. And given that the universe is about 94 billion light years wide, we’re talking some huge numbers.

As big as that is, pi is such a precise and useful number that we don’t need to use a lot to figure out the size of something so large. And even though some humans have memorized pi to thousands of digits, most of that isn’t necessary in any practical way. Just ask NASA. When they do calculations, they use pi to only 15 digits.

When calculating the observed universe, which is the distance from earth to Voyager I which is over 12.5 billion miles away, using 15 digits of pi to cover the 25 billion mile diameter leads to an answer that will only be off by 1.5 inches. That’s close enough that there’s no need to worry about extra decimal points.

If someone wanted to get more precise, using pi to 40 digits could calculate the size to within a single hydrogen atom.

## 7. A Swiss University Calculated Pi to 62 Trillion Digits

Speaking of pi, if we only need 15 digits, what’s the point of calculating it any further? Well, you could ask what’s the point of calculating anything if that’s how you want to be. Sometimes it’s just an interesting thing in and of itself.

In terms of the actual numbers, the World Record holder for a person memorizing pi is Suresh Kumar Sharma, who memorized the number to 70,030 digits. That’s just what a human mind can recall. When you look at computers, things get out of hand.

Records get broken every few years as newer and more powerful computers are tasked with the job, but in 2021 a Swiss University set the baffling record of calculating pi to 62.8 trillion digits. That beat the previous record by nearly 13 trillion. That record was set in 2020. Before that, Google had the record of 31.4 trillion in 2019. Depending on when you come across this, the record may be broken again. And again. But it’s only going to get more and more unbelievable.

The Swiss record took a computer 108 days to calculate. They used two AMD CPUs with 32 cores each, a terabyte of RAM, and a 510 terabyte hard drive. The number alone used 63 terabytes. One terabyte can store about 250 movies.

## 6. James Bradley Closely Calculated the Speed of Light in 1728

When you’re talking speed, few things in the universe are ever going to be faster than the speed of light. In fact, many scientists would argue that nothing will ever be faster than the speed of light. The precise speed is calculated at 299,792,458 meters per second. That works out to 670 million miles per hour. You can imagine a lot of precision tools are used to calculate something so fast. But they don’t have to be.

James Bradley calculated the speed of light to be about 300,000 kilometers per second. Based on the above, it’s actually 299,792.458 kilometers. So he was awfully close. And he calculated that in 1728.

Bradley’s calculations were based on stellar aberration, that stars looked like they were moving based on the Earth’s movements. He made a calculation based on the speed of the Earth’s orbit and the angle of aberration to come up with an extremely close result.

## 5. Matter Is Only About 5% of the Universe

We pointed out earlier that the entire universe is about 95 billion light years across. So what fills that space? Obviously, a lot of it is just space. But there are things floating around in it, and a lot of it we can’t see.

An easy way to understand what makes up the universe is to break it up into three basic substances. Matter, dark matter, and dark energy. Matter is you, your dog, the moon, cats, and everything else we can see and touch including all the planets everywhere. It’s been calculated that all of that stuff makes up around 5% of the universe. It could be as high as 10% and some estimates have it as low as 1%. So all matter, everything physical, could just be 1% of the entire universe.

Our current understanding, and that could very well change as we learn more about the universe, is that 70% of the universe is dark energy and 25% is dark matter. Of course, it’s possible that there’s no such thing as dark energy at all, too. Science can answer few questions about it, so there’s a lot of guessing involved.

## 4. Thomas Dick Calculated the Population of the Solar System at 22 Trillion

Not every calculation has to be accurate to be impressive. That’s the case with Thomas Dick who, in 1837, calculated the population of the solar system to be 22 trillion life forms. In his figuring, there were 4.2 trillion on the moon alone.

Dick’s calculation wasn’t just pulled out of thin air, he tried to put some thought into it. The population of England was 280 people per square mile at that time. So, he concluded, every single surface in the solar system was likely the same. Actually, not just likely, but certainly. He was positive because, in his figuring, God wouldn’t make all that space just to waste it.

There were seven trillion aliens on Jupiter alone based on this calculation. Venus would have had a slim 50 billion citizens.

## 3. The World’s Biggest Math Problem Took 200 TB of Text to Solve

What would you consider to be the biggest math problem you’ve ever solved? In high school, most of us had to at least do one of those equations that took up an entire page in a notebook solving for x or determining the angle or something or other. Those have nothing on the world’s biggest math problem.

In 2016, three math experts worked for two days to solve the world’s biggest math problem. It was a decades old puzzle that no one had cracked until then. Probably because the calculation was so large it comprised 200 terabytes of text. That works out to the equivalent of everything in the Library of Congress and would require a 30,000 hour download and verification time. The three were awarded $100 for solving it.

## 2. The Wait Calculation Determines When Taking a Space Voyage is Pointless Because Tech Will Improve To Shorten The Trip Before You Arrive

If you consider space travel today, if you wanted to visit another star, it could take 6,000 years. That’s completely unreasonable. But space travel today is better than it was 50 years ago, right? So if we waited another 50 years, how quickly could we reach that star? Part of the calculation involves estimating the growth of technology and our ability to do things faster and more efficiently in the future.

There’s some serious estimation here regarding how technology advances and what that would mean for space travel. But the general idea of the Wait Calculation is that if somebody set out for that star today, in 50 years another team could set out and get there much faster, passing that first team. And in another 50 years, a third team could surpass both the first two teams.

There is a point when the wait becomes a detriment and eventually you’ll waste more time waiting than traveling.

## 1. Internal Monologue Was Calculated at 4,000 Words Per Minute

Not so long ago, a good number of people on social media were hit with the realization that not everyone in the world has an internal monologue. Conversely, many people realized that many people in the world do have an inner monologue. The result of this is the knowledge that people think differently from one another, so you shouldn’t make assumptions about what’s going on in someone else’s head.

For now, let’s just focus on the people who have a monologue. How fast does your brain come up with the words that it uses to fill in that monologue? In the year 1990, someone tried to calculate it. The number they came up with was 4,000 words per minute.

This is far faster than external speech, somewhere in the neighborhood of 10 times faster than you could speak out loud, and doesn’t have to be a string of coherent words and sentences by any means.