Each of the dice has numbers 1 to 6 on the sides. There are 6 times 6 ways in which the numbers in the dice can be paired (e.g. 1-1, 1-2, 2-3, 4-4, 5-1, etc). Now, to get a number 1 from 1 die and 2 from the other, the dice must be rolled at least 36 times.