is that 17 can not be divded by three without having a fraction, so the judge addid his camel to have 18 which can be divided by 3
The father already died and left the 17 camels for his sons, and the sons did not how they can divide the camels as per their father wishes.
17/2 = 8.5
17/3 = 5.67
17/9 = 1.89
Now = 1.89 + 5.67 + 8.5 = 16.07 so there is one camel left and I can say this is not fair
here what the judge did
17 camel + Judge camel = 18 camels
18/2= 9
18/3= 6
18/9= 2
Now let us see 2+6+9 = 17 and remaining camel took by the judge which obviously his camel.