Question

Find the probablity of getting a sum of at least 8 by tossing a six-sided die twice.

I keep getting 5/36 but my book says 5/12.

Answer 1

Of the 36 possibilities, when tossing the same die twice, the ones that give a sum of 8 or more are:
6,2; 6,3; 6,4; 6,5; 6,6
5,3, 5,4, 5,5, 5,6
4,4; 4,5; 4,6
3,5; 3,6
2,6
That is 15 out of 36, for a 5/12 probability of 8 or more.

That is also the probability of tossing eight or more with two dice.