The triplets, nick, brian, and dan, exit their preschool classroom every day in a random order. create an organized list to show the possibilities. give the probability that nick will exit first followed by brian and then dan, or p(nbd)

The set of all possibilities is called sample space and is denoted by S.

So, S = {NBD, NDB, BDN, BND, DBN, DNB} and n(S) = 8

and we need to find the probability of NBD

E = {NBD} and n(E) = 1

The probability of an even is defined by p(E) =

Hence,  p(E) =