Question 1132893: Two dice are rolled. Determine the probability of the following.
Rolling an even number or a number greater than 9
Answer by Alex.33(110)   (Show Source):
You can put this solution on YOUR website! I'll now assume the "number" in your question to be the sum of the number given by the two dice. (Otherwise it is not possible for a typical dice to roll a number >9)
The total number of possible outcomes is 6*6=36 cases.
a. To get an even sum, the two numbers are supposed to be even+even(3*3=9) or odd+odd(3*3=9)/*this is simple number theory, simply provable*/, with a total of 18 cases under this condition.
P(an even number)=18/36=1/2. /*since this is a classical probability question, I use the classical definition here, although it is actually somewhat non-rigorous in logic. If curious you can visit wikipedia: probability.*/
b. To get a number greaer than 9, there are 3 kinds of cases:
sum=10: 4+6, 5+5, 6+4.
sum=11: 5+6, 6+5.
sum=12: 6+6.
A total of 6 cases.
P(a number greater than 9)=6/36=1/6.
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