The areas of statistics and probability are my favorite in mathematics. This is because I like to be able to draw conclusions from data and predict the future with past trends. Probability is also fascinating to me since it allows us to make more educated decisions about real-life events. Since we are supposed to get a big snow storm in Waterloo, I thought I would write a blog post discussing conditional probability using the Probability Tree Generator, created by Miles Simmons.

If the probability of snowfall on any given day during a Waterloo winter is 0.75, the probability that the schools are closed given that it has snowed is 0.6, and the probability that the schools are closed given that it has hasn’t snowed is 0.1, then we get the following probability tree, created by Miles’s learn document:

From this information we can come to some interesting conclusions:

What is the probability that the schools are closed on a given day?

From the Law of total probability, we get:

Thus, during a very snowy Waterloo winter, we could expect a 0.475 chance of schools being closed on any given day. 

One of the features of this document is that the node probabilities are calculated. You can see this by comparing the second last step to the number at the end of probability trees' nodes.

What is the probability that it has snowed given that the schools are closed?

From Bayes’ Theorem, we get:

Thus, during a very snowy Waterloo winter, we expect there to be a probability of 0.947 that it has snowed if the schools are closed. 

We can also add more events to the tree. For example, if the students are happy or sad given that the schools are open:

Even though we would all love schools to be closed 47.5% of the winter days in Waterloo, these numbers were just for fun. So, the next time you are hoping for a snow day, make sure to wear your pajamas inside out and sleep with a spoon under your pillow that night!

To explore more probability tree fun, be sure to check out Miles’s Probability Tree Generator, where you can create your own probability trees with automatically calculated node probabilities and export your tree to a blank Maple Learn document. Finally, if you are interested in seeing more of our probability collection, you can find it here!

Have you ever wondered who the students are that help create Maplesoft’s family of products?

In this blog, we thought that it was fitting to introduce ourselves and give the MaplePrimes community some insight into the students who are committed to helping Maplesoft improve its products and who believe that Math Matters!

I’ll begin. My name is Jack Thomson and I’m in my second year of the Mathematics (Waterloo) and Business Administration (Laurier) Double Degree. This term I am the Product Management Co-op at Maplesoft where I will be helping support the development of Maplesoft's academic market products, including Maple Learn and Maple Calculator. My favorite areas of math are statistics and probability. These areas are my favorite since I like to be able to draw conclusions from data and predict the future with past trends. I am also fascinated with probability since it allows us to make more educated decisions about real-life events. This ties into my belief of why Math Matters, since it is hidden in every aspect of life and helps us understand the world around us. Besides my love for the world of mathematics, I love the outdoors, more specifically, mountain biking, backcountry camping, and skiing. I also enjoy taking photos, watching Formula 1, playing hockey, and improving my skills in the kitchen.

Continue reading below to find out more about my fellow Co-op students!

Development:

I’m Zhengmao (he/him), and I’m a third year in Software Engineering at the University of Waterloo. I’ll be working until the end of April here at Maplesoft as a Software Developer, where I’ll be working to fix bugs, add new features, and improve existing ones for our Maple Learn as well as Maple Calculator products. By the way, if you ever have any suggestions or ideas about them, don’t hesitate to reach out to me!

I’ve always been curious about working at a math company because I’ve always been so interested in math. In fact, Maplesoft is the only company I’ve consistently applied to every time I’ve gone through the Co-op application cycle! However, there’s not really any particular reason why I enjoy the subject. I find math to be beautiful in and of itself, almost like an art, and I find the kinds of math that are more discrete or algebraic tend to be a little nicer. As long as there aren’t decimals, I’m pretty happy. So, my ideal kind of math is just that: ideal! Exact values, unrealistic ideas, and as few numbers as possible. In terms of my university career, I’ve always enjoyed linear algebra much more than calculus.

Overall, I’m quite excited for this term at Maplesoft. I’ve never worked in web or mobile development before, so I’m looking forward to learning a lot of new things!

Content Creation:

Hi, I’m Paige (she/her). I am a second-year Honors Mathematics student at the University of Waterloo. This term, I am creating content for the Maple Learn document gallery. My favorite area of math is calculus because I love visualizing functions. Math matters because it is a universal language. All the math concepts we know are naturally occurring; people have observed and documented them, but no one invented them. Because of this, people from a wide range of cultures have come to the same conclusions (ex: defining pi). Math is universally understandable, which is why it can be used to connect everyone on earth (and maybe on other planets too!?!?!?!). In my free time, I like doing hand embroidery, playing video games, and cuddling my cat Licky.

My name is Laura (she/her) and I’m a second year in the math program at the University of Waterloo. This term, I am working as a ‘Math Content Developer’ at Maplesoft; I’ll be creating and scripting documents for Maple Learn’s Example Gallery, updating older content, and handling customer requests. My favorite areas of math are probability, since I find questions like the Birthday Problem interesting, and biostatistics because I enjoy learning about biology and how biological experiments can be analyzed mathematically. I believe math matters because mathematics is essential to sending equipment and people into outer space; we will never meet aliens without using math.

Quality Assurance:

Hey, my name is Stefan, I'm 19 years old and currently studying Biochemistry in second year at the University of Waterloo. I am a QA analyst here at Maplesoft, working on Maple 2023. Outside of school, a hobby of mine is making digital art. My favorite area of math is definitely calculus & analysis because I found learning the fundamental theorem really intuitive and engaging. Expanding on that, I believe math matters because of its many applications in other fields such as the use of calculus in the research and design aspects of Biochemistry.

Hey! My name is Steven Mou, I'm in CFM at UWaterloo and I'm going into my 2B term after this term. I'm one of the four QA Analyst interns and I'll be testing all things related to Maple. My favorite area of math is anything related to algebra. I just find being able to manipulate variables while maintaining the integrity of the final product, to be very fascinating. I believe math matters because our lives are pretty much completely founded by math; anything from the technology that we use to the logic that is the foundation of our thoughts. I like playing sports, dabbling with different recipes in the kitchen, and discussing any shows that I happen to always finish too quickly.

Hi, my name is Aidan and I'm a 3rd-year mathematical physics student working as a quality assurance analyst for this Co-op term. As a Co-op student working in QA, I will mostly be running tests and reporting bugs to help ensure that Maple 2023 as well as Maple Flow are ready for release. My favorite area of math is vector calculus because as I started learning it I found it very interesting in the ways it applies to things we use in our everyday life. It also combines Linear Algebra and Calculus in a way that I never would have expected before learning about it. I think that math matters because I feel as though everything you can interact with can be described and predicted mathematically and that amazes me.

Hello! My name is Sebastian, I am currently in my second year of physics and astronomy at UWaterloo, and for this Co-op, at Maplesoft, I am working as a quality assurance analyst. In this position, I will be performing tests on Maple and Maple Flow to ensure that when they are released they function as they should and are ready for consumers to use with ease. When I am not focused on my academics I enjoy spending my time playing soccer (also watching it), listening to music, and watching movies. My favorite area of math is calculus because of the interesting and complex problems it provides, and because it is an essential tool needed to understand how the universe works. I believe that math matters because, as teachers always remind us, it is all around us. Math provides the foundation for everything we know and have come to appreciate in our lives, so since it is seen so often in our lives, I believe we should put in the effort to understand it and grasp how cool it is.

Happy Lunar New Year to everyone in the MaplePrimes community, as we enter the Year of the Rabbit. The rabbit symbolizes longevity, positivity, auspiciousness, wittiness, cautiousness, cleverness, deftness and self-protection!

To celebrate, one of our Maple Learn content developers, Laura Layton, made a Lunar New Year Color by Number:

In this puzzle, your goal is to simplify the modulo equations in each square, and then fill in the square with the color that corresponds to the answer.

I hope you have fun solving this puzzle and revealing the hidden images and I wish everyone good health and happiness in the coming year!

Last week, one of our Maple Learn developers, Valerie McKay-Crites, published a Maple Learn document, based on the very popular Maple application by Highschool Teacher, Jason Schattman called "Just Move It Over There, Dear!".

In the Maple application, Schattman explains the math behind moving a rectangular sofa down a hallway with a 90-degree turn. In the 3D Moving Sofa Problem Estimate, Valerie uses Schattman’s math to determine the largest rectangular sofa that can be taken down a flight of stairs and down a hallway with a 90-degree turn. Both applications reminded me of how interesting the Moving Sofa Problem is, which inspired me to write a blog post about it!

If you’ve ever been tasked with moving a rectangular sofa around a 90-degree turn, you might wonder:

What is the largest sofa that can make the move?

Following these steps as outlined in Schattman’s "Just Move It Over There, Dear!", will guarantee that the sofa will make the turn:

1. Measure the width of the hallway (h)
2. Measure the length (L) and width (w) of the sofa.
3. If L + 2w is comfortably less than triple the width of the hall, you'll make it!

When we work out the math exactly, we see that if the sofa's length plus double its width is less than , the sofa will make the turn!

This problem is easy if we only consider rectangular sofas, however, the problem becomes significantly more complex if we consider sofas of different shapes and areas. In mathematics, this problem is known as the Moving Sofa Problem, and it is unsolved. If we look at a hallway with a 90-degree turn and legs of width 1 m (i.e. h = 1 above), the largest known sofa that can make the turn is Gerver’s Sofa which has an area of 2.2195 m², this area is known as the Sofa Constant. Gerver’s Sofa, created in 1992, was constructed with 18 curve sections:

Check out this GIF of the sofa moving through the turn. It provides some insight into why Gerver’s sofa is such an interesting shape:

What is fascinating is that no mathematician has yet to prove that Gerver’s sofa is the sofa with the largest area capable of making the 90-degree turn.

The Moving Sofa Problem, is a great example of how math is embedded in our everyday lives. So, don’t stop being curious about the math around you as it can be fascinating and sometimes unproven!

If you are curious to learn more about the moving sofa problem check out this video by Numberphile, featuring Dan Romik from UC Davis: https://www.youtube.com/watch?v=rXfKWIZQIo4&t=1s