In a recent newsletter, well known scientist Katherine Hayhoe mentioned a listing of the top most efficient computers – while efficiency is something to consider in your purchases, is there really a big difference in which laptop you buy and use?

Continue reading “Computer efficiency numbers – useful rating or greenwashing?”## Another look at Zipf’s law, and you can chart it yourself!

In a previous post I showed some interesting facts about Zipf’s law and how many different things show a pattern of logarithmic decrease with the most popular or numerous item largely being much more so than the very rare ones – in a logarithmic pattern. Let’s look at that pattern and how you can chart it…

Continue reading “Another look at Zipf’s law, and you can chart it yourself!”## What day is Pi Day?

Today is Tuesday, Pi day (3/14)! Pi day is a national holiday celebrating mathematics, pi, and yes sometimes some baked pie and Pi-zza…

As 3/14 is a Tuesday, so are April 4, May 9, June 6, July 4, August 8, September 5, October 31, November 7, and December 26th!

Last year Pi day was on a Monday, the year before, a Saturday. Back in 2000, Pi day was Tuesday… Check out the math trick that lets you find the day of the week for *various dates throughout history*!: Check out James Grime’s full explanation of the trick:

## The Tic-Tac-Toe Magic Square trick

In *Mathematics Magic and Mystery* by Martin Gardner, the author presents an interesting card trick to create a magic square (where all rows and columns add to the same number), using an interesting interactive game with a participant. After playing a game of tic-tac-toe, your friends will be surprised to see they set up the cards in a 3×3 grid summing the number on the cards to 15!

## Puzzles – an open-source collection

Many mathematicians enjoy puzzles – and digging in to interesting code. Simon’s Puzzle collection is an open source collection of puzzles that any mathematician would enjoy:

Continue reading “Puzzles – an open-source collection”## Testing solutions to the 100-prisoners puzzle.

Both Matt Parker and the Youtube Veritasium channel have reviewed the surprising best practice for the 100 prisoners puzzle. The puzzle is a way to find a solution that will let the prisoners win with the most probability. If you have not seen this already please see the video here before some spoilers below.

Continue reading “Testing solutions to the 100-prisoners puzzle.”## Happy Pi Day 2022

Once again it is Pi day, a great time to make pie – or order a Pizza or Pie (check if your local restaurants have a special Pi day deal ðŸ™‚ )

This year Pi day comes on a Monday, which hasn’t happened since 2016! There are some interesting tricks to calculating what any given day of the week was, and I’ll leave you with a video that James Grime published with some math tricks for the day of the week for any given date:

Continue reading “Happy Pi Day 2022”## Happy Twosday! and a Surprising Pi trick

In Ben Sparks’ video he shows a very interesting trick. On a decimal angle calculator run:

sin(1/5555)

If your calculator has more than the standard Ubuntu calculator’s digits of accuracy you could add even more repeating 5’s. The answer is approximately PI with extra zeros…

0.000003142

Since today is Twosday (**2-22**-2022 in any date format), here is a similar Tuesday math trick for the Python console:

```
from math import sin
sin(22/700000.0)
```

It is also .0003142… or approximately Pi!

Continue reading “Happy Twosday! and a Surprising Pi trick”## Zipf’s law, Kleiber’s law, and finding interesting patterns in browsing history

In the chapter The Long Tail of the Law, in Alex Bellos’ book *The Grapes of Math*, he shows some different statistical patterns that share the same properties:

## Sum/product of consecutive numbers and other math shortcuts

If you have studied some of the old SAT questions at some point you may have gone through questions like –

4 consecutive numbers sum to 166. What is the product of the numbers? or…

3 consecutive even numbers sum to X. What is their product?

The way the tutors and the online tutorials show seems to always be to algebraically solve this – for example 4 consecutive numbers would solve x+x+1+x+2+x+3 = 166, collect terms and solve…

However there is another way that works for this and works for other similar problems.

Continue reading “Sum/product of consecutive numbers and other math shortcuts”