Three coworkers would like to know their average salary. However, they are selfconscious and don't want to tell each other their own salaries, for fear of either being ridiculed or getting their houses robbed. How can they find their average salary, without disclosing their own salaries?
The first person divides his salary into the sum of two different numbers.
The first person gives the first of his numbers to the second.
The second person adds his number and gives this sum to the third.
The third person adds his number and gives the sum to the first.
The first person adds the other part of his number.
As long as no one sees what number the others are adding they cannot figure out what these numbers are.
(You could also have each person divide their salary and have the running total go around twice.)

Posted by Jer
on 20130401 11:22:19 