first divide it into 3 groups... 4 for each group...公仔箱論壇# p4 x8 N5 z* b, K$ j& l
den use 2 groups to test... if the weight is same... den throw away these 2 groups.. if not... use another 1 group to test with tat 2 groups... throw away the same weight groups...
, l3 ] y1 d* b$ d2 t1 l4 q) c5.39.217.77:8898den... left 4 balls...
- n2 M$ Z* z( }( A6 itvb now,tvbnow,bttvbwhen u use tat 3 groups to test... u oredi know it is heavier or not...tvb now,tvbnow,bttvb; W5 Z: z8 e& N: @1 C) R
so when testing these 4 balls... u juz nit 2 find out the heavier or lighter 1...
* s* F0 n O l: Q% p6 ?2 M公仔箱論壇take the heavier or lighter 1... throw away tat 2 normal ball...5.39.217.77:88983 W9 o# u5 b3 O
den u juz nit 2 test the last 2 balls...
" D" @6 p" [( U5 P4 G$ T, P: n5.39.217.77:8898same for now... take the heavier or lighter 1... |