The first \(9\) natural numbers are given in a list. You are supposed to select two numbers randomly from the list, call them \(x\) and \(y\), remove them from the list and insert \(x + y + xy\) into the list. You keep repeating this until you are left with only one number in the list. Which number is most likely to be the last number left in the list?
Thursday, February 17, 2011
Please email your solutions to firstname.lastname@example.org.
This puzzle is taken from folklore.
The following is a list of resources on related topics:
- Wheeler, David A. "When Adding and Multiplying are the Same." 10 Sep. 2002. 9 Sep. 2011 <http://www.dwheeler.com/essays/add-multiply.html>.