1a. Ali has 8CDs that he is going to give away. He lets his best friend choose2of the8CDs. How many different groups of2CDs are possible? 1b. Omar has been given a list of 5bands and asked to place a vote. His vote must have the names of his favorite, second favorite, and third favorite bands from the list. How many different votes are possible? Solution a) Total 8 CDs Friend selects 2 CDs Possible combination : 8C2 = 8!/2!6! = 56/2 = 28 b) There are five possibilities for the favorite. You have picked a band as your favorite, that only leaves four different bands as your possible second-favorite, there are four possibilities for your second place So, possible different votes = 5*4*3 = 60.