When two dice are rolled, how do you find the probability of getting a sum of 6 or 7?

1 Answer
Jul 21, 2016

Probability of getting a sum of 6 or 7 is #11/36#.

Explanation:

When two dices are rolled , there are #6xx6=36# outcomes of the type #(x,y)#, where #x# is outcome of first dice and #y# is outcome of second dice. As both #x# and #y# can take values from #1# to #6#, there are total #36# outcomes.

Of these the outcomes #(1,5)#, #(2,4)#, #(3,3)#, #(4,2)# and #(5,1)# denote we have a got a sum of #6# and the outcomes #(1,6)#, #(2,5)#, #(3,4)#, #(4,3)#, #(5,2)# and #(6,1)# denote we have a got a sum of #7#.

Hence there are #11# outcomes (of the total of #36# outcomes) which give us the desired output.

Hence probability of getting a sum of 6 or 7 is #11/36#.