DECEMBER 1997

 There were 3 cannibals and 3 missionaries who wanted to cross a river, and there was only one boat that could only carry 2 people at a time. All the missionaries could row, but only one of the cannibals could. And as long as the number of missionaries and cannibals was even (on the boat or on shore) everything was o.k., but as soon as the cannibals outnumbered the missionaries, they would eat them up. Can you cross them all without loosing anyone?

ANSWER

 Start situation.

First 1 missionary and a cannibal (not the one who knows how to row) cross.

The missionary comes back.

Then the rowing-cannibal and the other cannibal cross.

The rowing-cannibal comes back.

Two missionaries cross over.

One missionary and a cannibal row back.

The rowing-cannibal and a missionary cross again.

The missionary returns with the other cannibal, leaving the rowing-cannibal on the other side.

The two left over missionaries cross, putting all three missionaries on the other side of the river.

The rowing-cannibal has to make two trips to go get the other two cannibals (one by one) left on the other side of the river.