i thing the answer istvb now,tvbnow,bttvb& J' Z$ i; n! ^# Q
start with 4 on each side of the scale,this will have two possible outcome, same or diff.tvb now,tvbnow,bttvb) a2 N0 K. }/ v# H9 D4 {4 \: u4 Y
If the same then 4 that left over contain the odd ball. put 1 of the 4 to each side, two outcome, same or different again. Replace 1 from the remaining, if the same then left over is the odd or if different the replacement is the odd one. I didn't time myself but I think I take less than 30 minutes. There are two more possible out come but still need three weighing but I think I am running out of space. |