# Category Archives: Applications of Math

Links to articles detailing how math is used in the real world

# And The Gold Goes To…Rounding!

Can rounding have an impact on the real world?

In the case of the Olympics it certainly can. In the Women’s Downhill event this week, two women were awarded the Gold medal in a tie. However, they did not record the same time. This was because of rounding.

# Wired Magazine: The Man Who Could Unsnarl Manhattan Traffic

The article “The Man Who Could Unsnarl Manhattan Traffic” appeared in Wired magazine in 2012. At the time I thought it was very interesting considering that the person it describes, Charles Komanoff, did all of his work using Excel. And you all thought I was torturing you with learning spreadsheets for nothing.

Komanoff has created a model for traffic and all of the different factors that impact traffic flow in Manhattan. And he did all of this with statistics and Excel! Excel, like Google Sheets, is a standard business tool used in the real world. Learning the basic while taking this class should help you when you go looking for a job or when you take an accounting class.

Every graph you see in the handouts for your class is produced using Excel or Google Sheets…I get some pretty impressive results. And a lot of you are getting very good at using Google Sheets as well as Google Docs too. Learning how to use these tools will pay off…if not in this class then perhaps in other classes.

# Math Majors Make Big Mistake

Evidently they did not check their calculations adequately.

# Rogue Waves

What happens to those big container ships as they cross the Pacific. Some of them bring you all of the imported merchandise you have become used to…but some of the ships never reach their destination.

Here is an article from the New York Times about such waves including some great photos…remember, the decks of these ships are over 75 feet high. The waves are going over the top of them.

http://www.nytimes.com/2006/07/11/science/11wave.html

# How Good Is Your PIN Number?

I saw this article recently about PIN numbers. In it, the most common PIN numbers are EXPOSED! For our purposes, how many four digit PIN numbers are possible?

To find this, think of each digit as a choice. Four pin numbers means there are four choices. There are ten ways (0 through 9) to choose each digit so the number of possible pin numbers is

$\displaystyle 10\cdot 10\cdot 10\cdot 10=10,000$

How does this change if we decide the first number must be 2, 4, 6, or 8? In this case, the number of ways to choose the first number is reduced to 4 so the total number of PIN numbers where the first number is even is

$\displaystyle 4\cdot 10\cdot 10\cdot 10=4,000$

Wow! That small change reduces the number of possible PINS by 6000.

Take a quick look at the article to see the crazy PIN that people use that will increase the likelihood that a thief will discover your PIN. Is what they are describing an example of empirical probability?