64 = 65 ??? - Printable Version +- HP Forums (https://archived.hpcalc.org/museumforum) +-- Forum: HP Museum Forums (https://archived.hpcalc.org/museumforum/forum-1.html) +--- Forum: Old HP Forum Archives (https://archived.hpcalc.org/museumforum/forum-2.html) +--- Thread: 64 = 65 ??? (/thread-212106.html) 64 = 65 ??? - Erturk Kocalar - 02-19-2012 My dad forward this to me. It proves 64 = 65. Not really. It took me 10 seconds to figure out what's wrong. http://img7.exs.cx/img7/6534/1388.gif I did click on the link; I'm using mac os; my computer is still fine. (If you are using windows, please click at your own risk.) enjoy. Edited: 19 Feb 2012, 3:09 p.m. Re: 64 = 65 ??? - C.Ret - 02-19-2012 Ah! Ah! That's a well know property, moving any colored shape makes algebra wrong ! Another illustration : Edited: 19 Feb 2012, 3:17 p.m. Re: 64 = 65 ??? - Erturk Kocalar - 02-19-2012 Very cool. I haven't seen these before. Re: 64 = 65 ??? (solution) - Dieter - 02-19-2012 All this - especially the well known property of moving colored shapes making algebra wrong ;-) - works because our eyes simply do not work sufficiently accurate to distinguish two very similar, yet different slopes in the red/green and blue/orange shapes (first example) resp. the red and green triangles in the second example. If you look more closely you'll notice that the slopes of the mentioned shapes are slightly different, so they cannot be arranged the way the final layout suggests. One the one hand it's 3:8 boxes, on the other hand it's 2:5. In other words: 0,375 vs. 0,4. Which is so close that the difference it is not obvious for the human eye. Dieter Re: 64 = 65 ??? - Gerson W. Barbosa - 02-19-2012 This picture might disprove the equality: Another interesting illusion: Re: 64 = 65 ??? - Paul Dale - 02-19-2012 Quote:Another interesting illusion: Lovely. I'd not seen this one before. - Pauli Re: 64 = 65 ??? - Ed Look - 02-20-2012 Way cool!! All of these are fascinating!