1. divide 6 and 6, both sides will not equal7 [6 o5 W, f% `
2. take any side of the 6, divide then 3 and 3, again both sides will not equal公仔箱論壇- @4 p; h% z2 @0 {7 {- _
3. take any 2 and weigh them5 Y. U+ l8 V1 J/ ?8 e0 W2 c6 i$ z) d
if they equal, the one left is the ball.