begin quoting Ralph Shumaker as of Sat, Mar 17, 2007 at 05:14:48AM -0700: [snip] > That reminds me of the SAT or ACT (or somesuch) many, many moons ago, > where a few students challenged (and eventually won against) a couple of > answers on the test. One asked, ~"If you have two triangular pyramids
"Triangular Pyramid" threw me a bit. They're talking about tetrahedra. > (four sides each) and join them such that one side of one is in full > contact with one side of the other, how many faces are left exposed? > A) 2 > B) 3 > C) 6 > D) 7 > > Your response was marked wrong if it was not D. What was the challenge argument? /me ponders It doesn't say that the tetrahedra have to be the same size. So if tetrahedron A is much much larger than tetrahedon B, then one face of B will be "fully in contact with" one face of A, but A will have all four faces exposed (but one slightly obscured). That gives 7. No other case comes to mind at the moment. -Stewart -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-lpsg
