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counting and probability intermediate

Problem

Twelve fair dice are rolled. What is the probability that the product of the numbers on the top faces is prime?
(A)
(B)
(C)
(D)
(E)
Solution
In order for the product of the numbers to be prime, of the dice have to be a , and the other die has to be a prime number. There are prime numbers (, , and ), and there is only one , and there are ways to choose which die will have the prime number, so the probability is .
Final answer
E