first divide it into 3 groups... 4 for each group...5.39.217.77, ?$ e& Y0 L, I$ h6 d% Q& z
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...
8 w0 n* I. g* E/ P+ N+ g% c2 v0 bden... left 4 balls...+ \- X- x: v) G, e7 I
when u use tat 3 groups to test... u oredi know it is heavier or not...
; _2 f Z. t& L9 `: X7 K5.39.217.77so when testing these 4 balls... u juz nit 2 find out the heavier or lighter 1...
9 i* t$ l P% B/ q; o2 Btake the heavier or lighter 1... throw away tat 2 normal ball...5.39.217.772 J ^/ _5 }$ r4 G p G B
den u juz nit 2 test the last 2 balls...
0 e% O3 d: r/ g' v" btvb now,tvbnow,bttvbsame for now... take the heavier or lighter 1... |