EXAMPLE 4.19 Downloading Music from the Internet

The multiplication rule is just common sense made formal. For example, suppose that 29% of Internet users download music files, and 67% of downloaders say they don't care if the music is copyrighted. So the percent of Internet users who download music (event ) and don't care about copyright (event ) is 67% of the 29% who download, or

The multiplication rule expresses this as