Have groups of 4 people act/solve this puzzle for some fun (add blindfolds if you want a good belly-laugh):
Once upon a time there were four people who wanted to cross a river.
There is a person who takes ten hours, a person who takes five hours, a person who takes two hours and a person who takes one hour. The boat moves at the rate of the slowest person.
They travel by boat to cross the river and the boat must be rowed by at least one person but can carry at most two people. Every time they cross the river or return to pick up another person counts as time.
They must cross a river in at most 18 hours.
Can you get all the people across the river in the limited time?
Show the method that would enable these four people to safely cross the river.
(There is a solution … posted in the comments)