Minimum 10K RunnersDiscrete Mathematics Level 4
A 10 km race has 5 water stations set up around the course. What is the minimum number of people that must run in the race in order to guarantee that 10 people stop at the same set of water stations?
Details and assumptions
A racer may stop at none of the water stations. (The set of water stations such a racer stops at is called the null set.)