Pi Approximation Day 2009 is Also a Pi BAD

MathBabbler tweeted the following on 22 July 2009.

   Today (7/22/09) is a Pi BAD (Basic Arithmetic Date): 
   22 / (7! / sqrt(9)!!) = 3.14 (Pi rounded to nearest hundredth). 

A couple of hours later Wolfram|Alpha tweeted the following.

   "In honor of Pi Approximation Day http://bit.ly/EmocA"

July 22 written in MM/DD format is 7/22. 7/22 doesn't approximate Pi, but if July 22 is written DD/MM, then 22/7 approximates Pi rounded to the nearest hundredth. [Note: Division is not commutative.]

MathBabbler discovered that some of his math expressions, which work fine with Google, don't work when entered into the Wolfram|Alpha computational knowledge engine.

         Google:  22/(7! / sqrt(9)!!)
   WolframAlpha:  22/(7! / ((sqrt(9)!)!))

22 July 2009 was not only Pi Approximation Day, it was was a Pi BAD (Basic Arithmetic Date).

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 22 July 2009

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