Question

Scissors bet par Paper beats rack Rock beats schoors Consider the game of rock-paper-scissors to be an experiment. In the long run, roommate A chooses rock 21% of the time, and roommate 3 chooses rock 61% of the time; roommate A selects paper 39% of the time, and roommate B selects paper 21% of the time; roommate A chooses scissors 40% of the time, and roommate B chooses scissors 18% of the time. (These choices are made randomly and independently of each other.) The probabilities were assigned using the subjective approach Define event B as the event that roommate B wins the game and thus does not have to wash the dishes. What is P(B), the probability of event B? O P(B) = 0.36 OP(B) = 0.43 OP(B) - 0.38 OP(B) = 0.67 the the went that the samelen in die

Answer 1

the probabilities were assigned using the empirical (relative frequency) approach

P(B) =P(A rock and B paper)+P(A scissor and B rock)+P(A paper and B scissor)

=0.21*0.21+0.39*0.18+0.4*0.61

=0.36

P(C) =0.21*0.61+0.39*0.21+0.4*0.18 =0.28

P(A) =1-0.36-0.28 =0.36

OB = event A or event C

probability of Bc =0.64