A standard set of dominoes contain 28 tiles, with each tile having two sides of dots from 0 to 6. Of these tiles, 7 have the same number of dots on each side. If four players each randomly choose a tile, without replacement, what is the probability, that each chooses a tile with the same number of dots on each side?
The first person has a 7/28 = 1/4 probability of choosing such a domino
The second = 6/27 = 2/9
The third = 5/26
And the fourth = 4/25
Multiplying these together, we have
(1/4) (2/9) ( 5/26) (4/25) =
(1/4) (2/9) (5/25) (4/26) =
(1/4) (2/9) (1/5)(2/13) =
4 / 2340 =
1 / 585 ≈ 0.17%