The traditional Sino-European domino set consists of 28 dominoes
u can tell by multiplying the most amount of dots that are on to itself. in other words: 6 dots times 6= 36 dominoes
Use the formula (n+1)(n+2)/2, where n is the number on the highest double in the set. For a double 12 set: 13 x 14 / 2 = 91. For a double 9 set: 10 x 11 / 2 = 55 For a double 6 set: 7 x 8 / 2 = 28
168
In a double six deck, 168.