## Essential University Physics: Volume 1 (4th Edition)

We see that there are $2^6=64$ possible options. a) Only one of these options will result in all molecules being on one side of the box. Thus, the answer is 1/64. b) We find that the number of possible ways this could happen is: $\frac{6!}{3!3!}$ This gives: 20 So, our answer is: $20/64=5/16$