A pilgrim needs to make a journey on foot between Casablanca and Marrakesh, to deliver movies to the new Marrakesh multiplex. It's an arduous and dangerous trip at best, and it takes six days. The most a traveler can carry for food and water is four days' worth.

I hope there's a hotel someplace in between.

There are no hotels. Here's the question: How many people must start out together, so that one of them can make it all the way to Marrakesh from Casablanca?

One other thing: the others who start out along with the pilgrim? They can't die along the way.