easy, one minutes i solve the problem
1 g& k! o: Q. n {* ndivide into half, mean 6/ 6
4 |: E2 ?9 f& ctake the heavier 6 ping pong
4 J: M D0 ~; @- N M8 |divide into 3/3, take the heavier 3
: |' ?' K1 L( Ftvb now,tvbnow,bttvbtake the the other 3 that have the equal weight, switch each to measure, the most important things is labeling the ping pong so that we can recognize |