Three perfect dice are rolled. Under the condition that no two show the same face, what is the probability that one of the faces shown is an ace (one)?

Step-by-step solution

When three dice rolled and no two show same faces aligned & n ( ~s )=6 5 4 & n ( E )= n ( one of the faces shown is an one )=3(1 5 4) & =3 5 4 & P ( E )= 3 5 4 6 5 4 = 1 2 aligned