Three dice are thrown at the same time. Find the probability of getting three twos’, if it is known that the sum of the numbers on the dice was six.

As three dice are thrown at the same time, so we have sample space [n(S)] = 63= 216


Let E1 is the event when the sum of numbers on the dice was six and E2 is the event when three twos occurs.


E1= {(1,1,4), (1,2,3), (1,3,2), (1,4,1), (2,1,3), (2,2,2,), (2,3,1), (3,1,2), (3,2,1), (4,1,1)}


n(E1) =10 and E2 {2,2,2}


n(E2) =1


Also, (E1 Ո E2) = 1







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