If you have 12 pigeons and there are only 11 roosts, then at least one roost will be quite cozy.
A family of \(121\) crows move into a new neighbourhood which has \(12\) identical birdhouses. What is the minimum number of crows that each birdhouse must be able to hold, in order for all the birds to fit?
There are \(22\) people in a party. Calvin, one of the participants of the party, shakes hands with \(18\) friends forgetting about the other three, goes to the washroom to wash his hands, and returns to the party. Then he again shakes hands with \(18\) friends, goes to the washroom, and returns to the party. He repeats this same pattern over and over.
Calvin sits down with some punch immediately after a final round of \(18\) handshakes in which Calvin shakes hands with one final friend who he's randomly managed to neglect all the rest of the evening. Sipping his punch, Calvin realizes that the numbers of handshakes with each of the \(21\) friends are all different. What is the minimum number of times he must return to the party, assuming that he always shakes hands with \(18\) friends after every return?
A theater is inviting \(2670\) total students from various schools to see a movie. Each individual school invited is only allowed to bring at most \(38\) students. If the theater has \(193\) seats in each row, how many rows do they need to set aside for schools in order to guarantee that all students from the same school can be seated in the same row?
Alice, Bob, Candice and David run for school president. There are \(201\) students in the school and each student can vote for only one candidate. The person with the largest number of votes is the winner. If every student votes, what is the minimum number of votes needed to win the election?
Details and assumptions
Ties for the winner are not allowed in this election.