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For October 2024, we will be reading Mathematics for Human Flourishing by Francis Su.

Please use this thread to post questions, comments, and reviews, at any time.

I am about 5 chapters in, taking a break from a different math book to read this one with the group so hopefully there's someone out there reading it!

Intuitively, I knew what needed to happen to solve the chapter 1 brownie problem. But I didn't really understand it until I read Chris's very simple explanation at the end of his letter in Chapter 4. And then I realized it's basic grade school geometry, though I don't remember them ever teaching us about brownies in grade school :-). I'm definitely going to try the chapter 2 sudoku puzzle.

I'm finishing last month's book but I'm eager to start reading this one. Nice to hear it has puzzles! I'm a fan of those.

I am listening to this. I will need to download the extra material included.

I am indeed enjoying the puzzles. I think it's worth the download.

There's a shortcut for multiplying by 11! Nobody ever told me this? Perhaps they didn't know. Book example: 81 X 11. Take the 8 and the 1 and add them together and then insert their sum in between to get the answer: 891.

I played around with it a bit and it works for 2 digit numbers but if you add those 2 digits and get a number 10 or greater, you have to remember to carry the 1.

Nice one! Don't know if the book mentions this but you can do a similar trick to elevate to the power of 2 any two-digit number.

Take 81, for example. Take the 1 and elevate that to the power of 2. This will be your first digit from right to left. If this is a number higher than 9, you carry it to the next digit.

Then, take the 8 and 1, multiply them, and multiply that by 2 (sum anything you carried on from the first step). In this case it's 16. Take the 6 and this will be your second digit from right to left. Pass the 1 to the next step.

Final step, take 8 and elevate it to the power of 2, so 64. Add 1 from the previous step and these will be you last digits.

You answer will be 6,561 (from right to left: 1 from the first step, 6 from the second step, and 65 from the final step).

No I did not know that! But I think I would have to practice that one a few times. There's a bit more to it.

Hector wrote: "Nice one! Don't know if the book mentions this but you can do a similar trick to elevate to the power of 2 any two-digit number."

Here's another little trick you can do in your head (maybe with a bit of practice). Ask someone to pick a multiple of 10 from 10 to 100. (Call it "a"). Now them to pick a number from 1 to 10, (Call it "b"). Then say that you will multiply a+b times a-b. Then you can immediately state the product, because it's simply a^2 - b^2.

For example, if a = 60 and b = 3, then the product of 63 x 57 is 3600 - 9 = 3591.

David wrote: "Hector wrote: "Nice one! Don't know if the book mentions this but you can do a similar trick to elevate to the power of 2 any two-digit number."

Here's another little trick you can do in your head..."

Nice! That builds on Hector's shortcut. I will be a hit at cocktail parties.

Unfortunately, I can not find the download.

I think I may be in the minority for this book, but unfortunately I just could not get into it. Here's a link to my full review, but I'll summarize some thoughts below: /review/show...

The main good: I really enjoyed the content in each chapter that involved Jackson, because it felt like the virtues and messages Su was aiming for were being brought to light and actually demonstrated. The interview with Jackson in the epilogue was also a favourite part, for the same reasons.

The main bad: I'm uncertain who the audience is for this book. Su says it's math novices, because he wants to show how anyone can engage mathematics. However, the self-help style, and mostly fluff content, made me instead feel he was preaching to the converted in order to make them change their approaches and stop scaring others away.

I just started this book and realized that I haven't done any significant math since college (many years ago). Really enjoying the book, and want to purchase math workbooks to improve my math skills. Wish I had a math teacher like him when I was in school.

Hayley wrote: "I just started this book and realized that I haven't done any significant math since college (many years ago). Really enjoying the book, and want to purchase math workbooks to improve my math skill..."

If you want some help, The Great Courses Plus has a streaming app that has some math courses that I really enjoyed and there are lecture notes you can download to go with the course. It allowed me to retake Algebra and Precalculus and now I'm on Calculus though I'm going pretty slow with it. I really liked the Precalculus class. I bet you could get it free at the library too.

Thank you Jessica! I'm on my phone and don't know how to quote you in a reply.

Hayley wrote: "Thank you Jessica! I'm on my phone and don't know how to quote you in a reply."

It's no problem and your welcome!

Jessica wrote: "David wrote: "Hector wrote: "Nice one! Don't know if the book mentions this but you can do a similar trick to elevate to the power of 2 any two-digit number."

Here's another little trick you can d..."

As I read the book further ... this trick is mentioned, along with many others!

I've been thinking about the problem, to prove that if there are 5 points anywhere on a sphere, at least 4 of them will be on or inside a hemisphere.

I can see this intuitively, but to prove it? Not so easy for me! (I'm still thinking about it ...)

I finished the book. It starts out great, with interesting mathematics puzzles and problems. But then it goes into philosophy, and becomes repetitious and boring.

I'm with you David, I have to admit that I skimmed through the final chapters pretty quickly. I liked the concepts behind each chapter but didn't think they all needed to be stretched out into full sized chapters.

I couldn't get into this book. I just didn't get what the author was saying, and it was too boring for me to work at it. Maybe it was just that so much else has been going on, with elections and all, that I couldn't focus, but there just wasn't anything that interested me in the first few chapters, so I gave up. Too many other things to tempt me away.