Question 617668
the 1st shell could be c, s, or m ___ 3 possibilities total


each of the three 1st possibilities, then has three 2nd possibilities ___ 3^2 possibilities total


this pattern keeps repeating, with each additional shell increasing the possible outcomes by a factor of 3


so picking up three shells has 3^3 possible outcomes


the probability that the 1st shell will be m, is one in three or 1/3