Chang has been given a list of 6 bands and asked to place a vote. his vote must have the names of his favorite and second favorite bands from the list. how many different votes are possible?

If Chang has a list of 6 bands, then he can select 1 from 6 to be his favorite band. There remains 5 bands, and Chang can choose 1 from those 5 to be his second favorite.
Using the product rule, he obtain 6·5=30 different possible votes.
30 possible votes