Consider a system of 3 molecules, A, B, and C. Suppose the 3 units of energy can be distributed over the three atoms where each atom can have no energy, one unit, two units or 3 units of energy. Assume each of the 10 possible arrangements is equally probable. What's probability that molecule C has some energy?

2 answers

Out of 10 combinations, three will have C with some energy.

Pr(3/10)
4/10!!!