A group of 100 customers at The Sound Garden were asked if they prefer to listen to
music by Phish or the Grateful Dead. People may choose both, and they may choose
neither. The results were:
• 59 people listen to Phish;
• 52 people listen to the Grateful Dead;
• 6 people listen to neither Phish nor the Grateful Dead.
Use the Principle of Inclusion/Exclusion to determine the number of people who listen to
BOTH Phish and the Grateful Dead. Show all work and/or explanations.