A black and red dice are rolled. Find the conditional probability of obtaining a sum greater than 9, given that the black die resulted in a 5

Explanation

If the event that the "blacl die is resulted in 5" is given then the possible elementary cases under consideration are reduced to (5,1),(5,2),(5,3),(5,4),(5,5),(5,6). Out of these 6 cases only two cases are favourable to the event that sum of the number rolled is greater than 9.
therefore Required probability =2/6=1/3.