Probability

 

A standard six-sided die is rolled twice. What is the probability that the product of the rolls is 1, 2, or 3?     

 

The number ways can you get a 1, 2, or 3 out of the number of ways the two rolls could have resulted.     

 

number of ways to get  1 ... 1, 1                   only 1 way     

number of ways to get  2 ... 1, 2   2, 1                  2 ways     

number of ways to get  3 ... 1, 3   3, 1                  2 ways     

 

total number of ways to get a desired product      5 ways     

total number of ways rolls could have landed     36 ways     

 

probability of rolling the desired product              5 / 36 or 13.9% if you prefer stating it that way     

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