Hi stumbled upon this interview question: There are 4 green and 50 red apples in a basket. They are removed one-by-one, without replacement, until all 4 green ones are extracted. What is the expected number of apples that will be left in the basket?
At first I thought it was 0, because there is always a chance for a green apple to be left in the basket, however since they are asking for the expected number of apples left, it actually makes sense that the number is positive. I found out that the answers is most likely 10, from various websites, however there is no solution anywhere. I have been trying to approach it with probabilities and with combination, however no luck so far. Some hints or a solution will be much appreciated.