Domino

Systematically checking the pip combinations across the board, every double-six domino appears except the 4-4 tile, which is absent.

The board shows the other doubles—0-0, 1-1, 2-2, 3-3, 5-5, and 6-6—but no 4-4 domino.

Pip readings from the small image are uncertain, but tallying the visible halves shows no 3-5 domino on the board, so it is the best guess for the missing tile.

The board shows 27 dominoes. Systematically checking all 28 combinations of a double-six set, 0-0,0-1,0-2,0-3,0-4,0-5,0-6,1-1,1-2,1-3,1-4,1-5,1-6,2-3,2-4,2-5,2-...

The board contains 27 dominoes. Enumerating the visible dominoes and comparing them against the 28 unique pairs in a double-six set shows that every pair appear...