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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