Since everyone by now who has any interest has gone directly to Catriona Shearer’s Twitter account for geometric puzzles, I was not going to include any more. But this one with its one-step solution is too fine to ignore and belongs with the “5 Problem” as one of the most elegant.
“Two squares sit on the hypotenuse of a right-angled triangle. What’s the angle?”
See the Two Block Incline Puzzle for a solution.
(Update 4/26/2019)Yikes! Another mental hiccup (though there is a more colloquial phrase). I just happened to reread the solution and discovered a misleading typo, which I have corrected. Proof-reading is clearly not one of my skills. I shudder to think of all the other mistakes in my postings.