With only D and E left, D keeps all 100, because his own vote is half. So with three, C only needs E, and one coin buys him. With four, B buys D with a coin. With five, A needs two more votes, and the cheapest are C and E, who would get nothing under B: one coin each.
Five pirates, ranked A to E from most senior, have 100 gold coins to share. The most senior pirate still aboard proposes a split, and everyone votes. If at least half vote yes, the proposer included, it stands. If not, he goes overboard and the next in rank proposes. Each pirate wants first to stay alive, then to get as much gold as possible, then to see others thrown overboard. They are all perfectly logical. What does A propose?
Give me a hintThe hint
Start with only two pirates left, and work backwards.
Reveal the answerHide the answer
98 for himself, and one each for C and E
Source: Ian Stewart, A Puzzle for Pirates, Scientific American, 1999