Question 1194661
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The solution from MathLover, as well as most of the examples on the link provided by tutor @ikleyn, solve the problem by looking at which outcomes in the sample space satisfy the given requirements.  That is, of course, a valid way to solve a problem like this.<br>
Another way to solve this kind of problem is to imagine rolling the two dice one at a time and considering the probability that each roll still makes it possible to get the desired end result.<br>
For this problem, the sum of the two dice must be 9.  Since the largest number on each die is 6, the outcome on the first die must be at least 3.  The probability of that happening (die shows 3, 4, 5, or 6) is 4/6 = 2/3.<br>
Then, once the first die has been rolled, for each number on the first die there is only 1 number on the second die that will give a sum of 9; so the probability of a "good" roll on the second die is 1/6.<br>
Then the probability of a sum of 9 is the product of the probabilities of "good" outcomes on the rolls of both dice: (2/3)*(1/6) = 2/18 = 1/9.<br>