###Human: A vampire drains three people a week. His best friend is a werewolf who eats five people a week, but only fresh ones, never drained ones. How many weeks will a village of 72 people last them both?, ### Assistant: The vampire and werewolf need 3 + 5 = 8 people a week.
A village of 72 people will last them both 72 / 8 = 9 weeks. 
 So the answer is :  9