The wise man read the Will patiently. The wise man, after giving due thought, brought one camel of his own and added the same to 17. That increased the total to 18 camels.

Now, he started reading the deceased fathers Will.

Half of 18 = 9. So he gave the eldest son 9 camels

1/3rd of 18 = 6. So he gave the middle son 6 camels

1/9th of 18 = 2. So he gave the youngest son 2 camels.

Now add this up: 9 plus 6 plus 2 is 17 and this leaves one camel, which the wise man took back!

Moral: 

The attitude of negotiation and problem solving is to find the 18th camel i.e. the common ground. Once a person is able to find the 18th camel the issue is resolved. It is difficult at times. However, to reach a solution, the first step is to believe that there is a solution. If we think that there is no solution, we wont be able to reach any!