hello1997

分3組4隻波子秤
! Y4 v% K6 r/ J  B. A" V0 C6 ?  y  V. D; w2 M
Group A: 1,2,3,4* U( X* }! ^% W  [% P
Group B: 5,6,7,8+ x4 C6 J$ o7 p0 `
Group C: 9,10,11,12- T/ O5 d* V+ S
Group D: 13  c) M/ Y  m  S
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Round 1
5 T3 V. V" E( l/ h( T0 U- VGroup A vs Group B, [  u/ n8 x$ H8 j0 n6 I
如A and B一樣, 即較輕一粒在Group C or D
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+ K9 ~5 h. O0 Y$ Y! ?, x2 o% DRound 2$ `- {9 B/ U$ v! [$ B# A3 O
再在Group C拆成:# q3 G3 c; i* W7 h: K7 u7 c, L! b
Group Ca: 9,100 s7 P; _3 n& [$ A0 S
Group Cb: 11,12
( {* `% }3 K, S0 R* x4 w  L然後再秤, 如一樣, 即13為較輕一粒.+ B: t/ f  _7 Y5 J' k3 H

: R+ G0 o# m# t; r/ S, s' q5 a" f: i如不同, 即較輕一組有一粒較輕波子在其中, 4 d3 a6 K$ y$ y. s
要再秤, Round 3, 之後便知答案.
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e.g. #1 假設10為較輕的一粒# s1 s# [9 l: p
Round 18 n# q. r$ l# x& Q
1,2,3,4 vs 5,6,7,8 = equal  i) x* i7 v9 Y1 C" p& D  W% \" H

* Q6 ?2 y& z2 N* K' ]4 D8 TRound 2/ Y+ [1 V. d. ]  I: ^3 t
9,10 vs 11,12 = 9,10 < 11,12  `0 s/ P. A7 c/ }2 N2 e/ S

  e! ~. @: Y$ D2 F+ H3 |Round 3
. H/ Z. N, F6 k' ]+ C9 vs 10 = 9 > 10
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The answer is 10.1 E5 u: p& i  {* L: J0 @" _6 ?
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e.g. #2 假設7為較輕的一粒. |" f% h! [. \, F# u4 q
Round 1: d' t) T' y8 ~- u6 p- @
1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,84 y: G- ]0 j7 ]4 l0 e+ {* m# N
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Round 24 }/ Q4 U+ f. f! p: Y, h& E
5,6 vs 7,8 = 5,6 > 7,8  I  ^# f& j: \. {+ p
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Round 3! Y+ C' h7 g. j+ C; K+ ?, x
7 vs 8 = 7 < 86 K& D+ L/ I; B

+ K$ \7 g5 c  _6 i5 b1 V$ H8 c9 sThe answer is 7.* r) b; A, H! j( f6 V* O
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e.g. #3 假設13為較輕的一粒
+ N0 z8 c0 y4 C' |, ^Round 13 g) c6 b0 ^( J; M! c  r
1,2,3,4 vs 5,6,7,8 = equal
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Round 2
& d6 R8 b) D: M# c9 i# {" q+ m9,10 vs 11,12 = equal
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7 e3 O  j( r% o  s* z: [" y3 }No Round 3/ |, M) ~- L& c! f, @; G1 B

2 A& @5 ~9 C& B+ d  C6 H/ LThe answer is 13.  X: ^. y  H7 ^8 x1 c
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唔知我答得正唔正確呢?!
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[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]