A group of five friends meet after many years on a get together.. They all wanted to know how well they are all doing.. So they all wanted to know the average salary of the group.. But none of them want to reveal their own salary.. Can you figure out a way and help them find their average salary without revealing their individual salary?? Come on.. My dear curious brains...
OK.. They sit in a circle . So the first member adds a number (say x) to his salary and says that to the second member. He adds his salary to it and says it to third member.. Similarly, third member adds his salary to it and says to fourth member, and fourth to fifth and fifty back to first.. Now the first member subtracts the number he added (x).. Now you get the sum.. He divides it by 5 and tells the average to the group.. Let me know if you have doubts.. Or if u are not clear with my explanation..
The secret is the sum doesn't change when you add and subtract the same random number to it.. This random number is used to hide the first person's original salary.. And average is sum divided by number of persons..