Refer to the IEEE Transactions on Information Forensics and Security (March 2013) study of wireless identify theft using cloned credit or debit cards, Exercise 6.3. On average, how many genuine balls will be drawn when 2 balls are randomly selected from the 10 balls?

Data from Exercise 6.3

Refer to the IEEE Transactions on Information Forensics and Security (March 2013) study of wireless identify theft using cloned credit or debit cards. A cloning detection method was illustrated using a simple ball drawing game. Consider the group of 10 balls shown below. Of these, 5 represent genuine credit/debit cards and 5 represent clones of one or more of these cards. The 5 letters—A, B, C, D, and E—were used to distinguish among the different genuine cards. (Balls with the same letter represent either the genuine card or a clone of the card.) For this illustration, let X represent the number of genuine balls selected and Y represent the number of B-lettered balls selected when 2 balls are randomly drawn (without replacement) from the 10 balls.