Actual Question : A fair die is thrown k times. What is the probability of sum of k throws to be equal to a number n?
My Work: Lets have k buckets, fill-in each bucket with value(1-6) so that the sum meets n, for every unique set of bucket values(u) find the no of *combination of arranging the values(x). Sum all x and the probability would be (sum of all x)/(6 power of k).
One way to find u is brute force. Is there any other way for that?
*I am not sure whether to use permutation or combination for that calculation x and I need formula for the same.