A group of 3 juniors and 2 sophomores is taking turns to take notes for a class that they are taking together
A group of 3 juniors and 2 sophomores is taking turns to take notes
for a class that they are taking together. Each time, they pick a student at random and do not pick that student again. Let X be the number of turns until and including the first time a sophomore is chosen. Write down the distribution of X and compute its expected value.