Problems from Independent event

The owner of a casino fakes two dices so that in dice A we can never get a 6 (and get twice as many ones), and in dice B we never get a 5 (and twice as many twos).

result dice A probability
1 ?
2 ?
3 1/6
4 ?
5 ?
6 0
result dice B probability
1 ?
2 ?
3 1/6
4 ?
5 ?
6 ?
See development and solution

Development:

  • The impossible events have zero probability (A=6,B=5). As we are been told, there is twice the probability of observing events A=1 and B=2 (probability 2/6):
result dice A probability
1 2/6
2 1/6
3 1/6
4 1/6
5 1/6
6 0
result dice B probability
1 1/6
2 2/6
3 1/6
4 1/6
5 0
6 1/6
  • Since the dice are independent, probabilities of the events are multiplied:

P(A=1 & B=3)=(26)(16)=118

  • Since it is impossible to observe A=6, the probability will be zero.

P(A=6 & B=2)=0(26)=0

Solution:

result dice A probability
1 2/6
2 1/6
3 1/6
4 1/6
5 1/6
6 0
result dice B probability
1 1/6
2 2/6
3 1/6
4 1/6
5 0
6 1/6

P(A=1 & B=3)=(26)(16)=118

P(A=6 & B=2)=0(26)=0

Hide solution and development
View theory