Riddle:
5 pirates are parting ways after finding a treasure of 100 pieces of gold. The pirates decide to split it based on a vote. Each pirate, from oldest to youngest, gets to propose a plan on how to split the gold.
If at least 50 percent of the other remaining pirates agree on the plan, that is how they will split the gold. If less than 50 percent of the pirates agree, the pirate who came up with the plan will be thrown overboard. Each pirate is smart, greedy, and wants to throw as many others overboard as possible without reducing the amount of gold they get.
What plan can the first (oldest) pirate propose to live and get as much gold as possible?
Show Hint
Hint:
You must think what each
pirate would do each time there is less
pirates than before. Imagine if there were just 2
pirates, then 3...
Show Answer
Answer:
He can propose a plan that he gets 98 pieces of gold, the 3rd
pirate gets 1 piece, and the 5th
pirate gets 1 as well.
If there were just 2
pirates the younger
pirate would
definitely deny the plan so he could get all of the gold.
If there were 3
pirates the first
pirate can offer the second
pirate 1 piece of gold and take the rest himself because the second
pirate wouldn't get anything if he has to propose a plan himself.
If there were 4
pirates the first
pirate could take 99 for himself and offer 1 to the youngest
pirate. They would both agree. If the youngest disagrees then he won't get any gold in the next plan.
So when there are 5
pirates it is in the interest of the 3rd and 5th
pirate to accept 1 piece, because if they don't they won't get anything in the next plan.