1. divide 6 and 6, both sides will not equal& Y0 p. X$ X# l
2. take any side of the 6, divide then 3 and 3, again both sides will not equal( Z; A. [: d# e4 r4 p
3. take any 2 and weigh them " V8 {+ m) P+ d8 l+ p公仔箱論壇if they equal, the one left is the ball.