Probability Question on dice: What is the probability that the sum of the two dice is a prime number?

[Te5]

Hello I’m trying to figure out how to work out the solution for the following:
What is the probability that the sum of the two dice is a prime number? The answer in the book is 0.4167 but I don’t know how to get this answer.

 

[MarkFL]

How many total outcomes are there when two dice are rolled?

 

[Steven G]

... and how many of them sum to a prime number?

 

[ImMAD]

Step 1: Calculate the values of possible sums with two dice, e.g. 1 is not possible, 2 is.
Step 2: For each possible value, determine if it is prime.
Step 3: For each possible value from step 1, try to find the number of combinations that allow for that value. For example, you can obtain 3 with values (1,2) and (2,1), 12 only with (6,6).
Step 4: How many total values are there for prime numbers, and how many in total? Can you find the probability from here?

 

[pka]

Hello I’m trying to figure out how to work out the solution for the following:
What is the probability that the sum of the two dice is a prime number? The answer in the book is 0.4167 but I don’t know how to get this answer.

Look at this expansion.
The term [imath]6x^7[/imath] tell us that there are six ways to roll a sum of seven.
The exponents range from two to twelve and the coefficients add to thirty-six.