Tangram Paradoxes
Tangram paradoxes are similar figures that are constructed of the same seven tans yet somehow appear inexplicably different from one another. The trait particular to paradoxes is that a piece of one figure seems to “magically” disappear on the other. In reality, there is no magic! The ever-so slightly different configuration of the tans creates enough differences in height and width, that though seemingly marginal, add up to create a deficit of space...ie. a missing piece!
One of the most famous paradoxes is the Dudeney Monk Paradox. The two monks appear to be the same except that one is missing a foot. In reality, the “missing foot” is incorporated into the bigger belly of the shorter, footless monk.
With the Magic Dice Cup Paradox, one of the cups appears whole while the others contain vacancies of some description. Closer inspection reveals that they are actually of slightly differing heights and girths. These slight spatial differences confer what appears to be “missing pieces of the cup”.