We know that A+B = 8 so we should first count the number of ways that the two dice could total 8. (A = 2, B = 6), (A=3, B=5), (A=4, B=4), (A=5, B=3) , (A=6, B= 2) -- this gives 5 possible waysWe also know that only one of these outcomes is (A=4, B=4) is the desired outcome. We know that each of these results is equally likely to occur because the dice are both fair and rolled independently so we can conclude the answer is 1/5.