In Ian Stewart’s book, *Professor Stewart’s Casbook of Mathematical Mysteries*, he writes about an easy way one might prove that the earth is not flat. His “easy” proof can be done by booking some flights and timing them… or, simply looking up actual flights from certain cities to other cities. If it is much much shorter for a certain flight from A to D while A to B to C to D in a nearly straight line is much longer, it’s effectively a proof you can go around the world without falling off…

## Happy Palindrome Day! Again and again!

As you may have heard, 02-02-2020 is a very “palindromic” day today. Especially so in that in either date formatting you use, the numbers are the same backward as forward (assuming you use *02 *not “2” that is). Matt Parker was quite excited, in fact he was beside himself in his latest math video:

## Euclid’s Doodle – and writing a visualization with Matplotlib

On page 110 of *Professor Stewart’s Casebook of Mathematical Mysteries*, he shows a neat visual way of calculating the GCD (Greatest common denominator, aka HCF, Highest common factor. Given a box with sides of two different lengths, draw squares from the lesser side until you can draw no more. Then continue from the corner the other direction. The smallest square has edge length of the GCD!

## Analyzing Scott Flansburg’s Nines Trick

There’s an old math trick that goes like so – choose any number… say 171…. add the digits and subtract.

171-9 = **162**

Take its sum of digits and subtract them…**162** – 9 = 153

Take its sum of digits and subtract them… Continue reading “Analyzing Scott Flansburg’s Nines Trick”

## Neural Networks Part 2: Learning Pi

Thousands of years ago, probably around the invention of the wheel, and before the time of Solomon, humans must have been measuring various objects… calculating some distances, and wondering, is there a better way to measure how far around the outside of a wheel is compared to its diameter? Continue reading “Neural Networks Part 2: Learning Pi”

## The only metric guide you may need

Kilometers, Centimeters… microfarads, farads… They units are all a multiple of 10, but that doesn’t make them that much easier as you are first learning them. What is 1.09km in cm? or 1205cm in km? With a quick jotted down note card you can very quickly see what any commonly used metric unit converts to!

## Think outside the box for the most optimal recycling solution.

Today we did some up-cycling of political ad signs. After elections these generally go in the trash, but Talent Maker City had a public event to build some cool stuff out of these corrugated plastic boards! *(Update- see the howto for version 2 of a durable cargo bicycle box here)*

Continue reading “Think outside the box for the most optimal recycling solution.”

## Candy-throwing Robot with Arduino, recycled parts, and Dlib

Looking for a fun way to hand out candies at your local harvest fair? In this howto I show how to use a wood frame and old computer/printer parts to build a robot candy thrower:

https://www.instructables.com/id/Candy-Throwing-Robot-With-Arduino-Recycled-Parts-a/