## Saturday, April 7, 2012

### A Weekend at Gathering 4 Gardner

I just spent last weekend at a conference in Atlanta, Georgia called Gathering 4 Gardner. This is a conference based on the interests of Martin Gardner, who wrote a math column in Scientific American as well as dozens of math, magic, and puzzle books. Though he did not do difficult mental calculations of any sort, he was the first person to hold the title of “Mathemagician.”
This conference had so many cool things, and I would like to share a few of these cool things. First off, I would like to mention a Fibonacci conversion that I learned. I know, it’s not Fibonacci day, but it is pretty cool.
Let’s say you want to convert from miles to kilometers. If you want to approximate 5 miles in kilometers, we would just go up to the next Fibonacci number. Since it goes 1, 1, 2, 3, 5, 8, five miles is eight kilometers.
What about a half-marathon. Well, minus .1 miles. After 13 comes 21 meaning that there are 21 kilometers in 13 miles.
What about 10 miles? Well, this isn’t a Fibonacci number, but you can still do it just fine. How can you create 10 as the sum of two Fibonacci numbers?

8 + 2 = 10
Now, just bring the 8 and the 2 up to the next Fibonacci number.
13 + 3 = 16
There are about 16 kilometers in 10 miles. This is all because the ratio of miles to kilometers is extremely close to the golden ratio; somewhere around 1.61. The golden ratio is the ratio of Fibonacci numbers, which proves this estimation system.
There were also a bunch of cool puzzles that I saw. Here is one of them:

For this puzzle, you have to try to move just one line to make the giraffe a different giraffe. Good luck! As usual, I will post the answer in around a month.
I also heard a pretty funny math joke at the conference that I thought I would share. Here it is:
A few people were inside of a cave and wondering if the cave makes an echo. So, they shout out, “We are lost.” A little later, they hear, “You are lost.” They then realize it was a mathematician and there are three reasons why. One, it took so long. Two, it was accurate. Three, it was completely useless.