Question

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)

Answer 1

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) = $\frac{n(E)}{n(S)}$

Hence,  p(E) = $\frac{1}{8}$