This has had me stumped for about 30mins. im assuming i should be using

P(A|B) = P(A&B)/P(B)

where

P(B) = Rolling a single 3 from both dices? or should this just be rolling a 3 on a single dice.

P(A) = Sum of the numbers = an even number, of which there are 2 option: 3+1 and 3+3

Answer is supposedly 3/7

If someone could give me some pointers on this id appreciate it.

Thanks