Jul 23 2013, 10:10 AM
Yes it is 20, don't/didn't you go to school guys o_O
First round put 3 on each side. If one side is heavier, then take those 3 for the 2nd weighing. If they stay the same, take the 3 that weren't weighed for the next round.
Second weighing, put 1 on each side, whichever is heaviest is that ball. If it's the same, it's the ball that you left out.
Fin.
First round put 3 on each side. If one side is heavier, then take those 3 for the 2nd weighing. If they stay the same, take the 3 that weren't weighed for the next round.
Second weighing, put 1 on each side, whichever is heaviest is that ball. If it's the same, it's the ball that you left out.
Fin.