A pair of six-sided balanced dice are rolled. What are the probabilities of getting the sum

of the face values as follows?

(a) 8

(b) 6 or 9

(c) 3, 8, or 12

(d) Not an even number

So I know the sample space is 36.

For (a) I got P = 5/36 b/c only 5 outcomes: (2,6) (3,5) (4,4) (5,3) (6,2) sum up to 8

For (b) I got P = 9/36

For (c) I got P= 8/36

For (d) I got P = 18/36 = 1/2

However, the book gives me these answers:

(a) 5/36

(b) 5/36

(c) 4/8

(d) 3/8

Am I doing something wrong?