Tue
Jun
22
Answer: Tuesday Teaser #18
The trick to this puzzle is to look at the glass side-on and imagine it in two dimensions as a simple rectangle. Now, if you tip the glass so that the water touches the rim of the glass, the water will form a line that approximately meets the opposite diagonal. If the line meets the glass above the opposite diagonal, then the glass must be more than half full and vice-versa.
