These popular tiles are used to play many games of Chinese origin, most notably Mahjong. Traditionally, the pieces were made of bone and backed with bamboo, but most modern sets are constructed from various plastics and contain between 136 and 144 tiles. The symbols on the tiles—the majority of which have a rank and suit like playing cards—are almost always engraved or pressed into the material. How do some expert players determine the face value of their tiles without actually looking at them? Discuss