
Photo by RBerteig.
Take a break from “serious” math and have a little fun today with some classics of recreational mathematics. Do you have a favorite math or logic fallacy? Please share it in the Comments below.
Story problem fallacy
Three Men in a Hotel Room
From the comments section at Let’s play math! blog.
Algebra fallacies
Classic Fallacies
Can you find the false step in each of these “proofs”?How to Double Your Salary Using an Algebraic Loophole
Another version of the beginning algebra fallacy, from WikiHow.
Geometry fallacies
Dissection Fallacy
63 = 64 = 65 from WolframMathWorld.What Is Wrong? (Rouse Ball’s Fallacy)
A geometry “proof” from Cut the Knot.
Edited to add
I found this spoof of a famous number theory joke in my feed reader this afternoon…
Proof: all April fools’ jokes are interesting
“Let S be the set of uninteresting April fools’ jokes…”
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Have more fun on Let’s Play Math! blog:



2 responses so far ↓
Lim Ee Hai // April 2, 2008 at 7:16 am
I suppose upon using this clock, we will get younger by the seconds. Hurray! I can rectify all the major mistakes made before using back the conventional clock…
Denise // April 2, 2008 at 8:23 am
LOL! I wish it were so.
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