Khushal u did great job. Ur answers are correct. The core of the Q5 solution is what u said. but its among 17 camals and not 18. Infact the solution provided by Hazrat Ali(a.s.) is as follows. He did add his one camal in 17 and it so becomes 18. The elder son gets 2/3. so 2/3*18 = 12 camals. The middle gets 1/6*18=3 camals. And the younger son gets 1/9*18=2 camals. So it sums upto 12+3+2=17 and thus one camal lefts back which was the one Our holy imam added for solving the problem.

there are still Q2 ,Q3 and Q6 are answered. I will post their solution on monday. So give a try. Best of luck

Jafery