Find the probability of a 4 turning up at least once in two tosses of a fair die.
The total outcomes = 36,
The favourable outcomes are (1,4), (2,4), (3,4), (4,4), (5,4), (6,4), (4,1), (4,2), (4,3) ,(4,5), (4,6)
Thus, the probability = favourable outcomes/total outcomes
⇒ 
1