odds in favour of rolling each of the following sums

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Dertermine the odds in favour of rolling each of the following sums with a standard pair of dice.
a) 12

so I know there is a total of 36 possibilities, but I dont know how to do this.
The answer in the back of the book is 1/35, I don't get how they only found one way..

thanks if you could help
 
There is only one way to get a 12. Out of 36 possibilities, that makes the probability of rolling a 12 the fracction 1/36. Your difficulty may be in the wording of the question or in the notation. Your book's "1/35" cannot mean a fraction, like my 1/36 above. The question asks for "odds". That is a different animal. I think it is confusing to write it as a fraction. I would prefer 1:35. In this way, the sum of values is 36 and the magnitudes are compared easily. The odds 1:35 is exactly the same as the probability 1/(1+35) = 1/36.

A background question, just to see if you are getting it...

A sign in a Physical Therapists office is trying to encourage kids to get an education. They are trying to make the point that it is very difficult to make it in the professional sports world. The sign says, "Your chances of making it in pro sports is 500,000 to 1...". Is this the intended message? Why or why not?
 
would it be opposite? 1: 50 000? because out of 51 000 people, the chance is one person to get into the sports world.

I get the dice one now, I for some reason thought there were more ways to make a 12.
 
Good call. It's either backwards or it should be reworded, "The odds against you making it..."
 
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