hello1997

分3組4隻波子秤5 Q  U0 E5 D  V7 l
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Group A: 1,2,3,4
8 [* ]/ b/ u/ m; [, ^# o# FGroup B: 5,6,7,8& i$ P8 a8 o. o0 x8 I) i2 |
Group C: 9,10,11,12
& K' x8 k) E' [0 I; |Group D: 13
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) ^, i6 C# w7 O5 ?$ F) S+ pRound 1
$ E( `3 A" l& |  T5 m7 O( SGroup A vs Group B
# O+ z1 G/ y; O$ ?9 ~如A and B一樣, 即較輕一粒在Group C or D
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Round 2
, _6 `# N; G4 B  Q  }再在Group C拆成:
  Y; M$ M) X$ P/ ?: `* LGroup Ca: 9,106 w* v& W( Q2 ?! ~7 D0 m( {* C
Group Cb: 11,12
- Z* X: z5 a) H0 A! Q然後再秤, 如一樣, 即13為較輕一粒.
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如不同, 即較輕一組有一粒較輕波子在其中, ) s; x5 n0 V9 e- q1 V
要再秤, Round 3, 之後便知答案.) K0 x! L, Y; p% E1 W+ `6 q

) A- [# Y4 o# v  a% ?  ~6 Se.g. #1 假設10為較輕的一粒) y  ~  e9 u2 R: o: _
Round 1
! O* M- [) c) t9 _1,2,3,4 vs 5,6,7,8 = equal
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+ _3 g6 Y0 I5 y% VRound 2
$ X+ c2 S; X0 x- d9,10 vs 11,12 = 9,10 < 11,122 `2 u4 k# t+ u2 b1 x

1 A' }  G' G, A) L2 O. Y& FRound 3' U- X+ k: M+ q  e; F3 S
9 vs 10 = 9 > 10( b+ J! f0 p3 o9 ^- n# G& F9 |8 _
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The answer is 10.5 h* G8 E& T- i' s( E" F/ H

2 ^: u2 v7 |& p0 a4 ne.g. #2 假設7為較輕的一粒
; \' Z2 X; L! j  Y; [/ TRound 19 K4 e# y; ~( i2 m
1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,86 K) ~$ H2 {7 D. l3 s

7 [) e7 U9 V$ x- P6 d2 q( V- iRound 2
6 l+ |, ]; w$ K: U+ Y5,6 vs 7,8 = 5,6 > 7,8
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# r& b3 _1 O4 l% J$ g3 q$ IRound 36 x7 m8 w  H# K  W& o$ ?$ b6 t; k* X
7 vs 8 = 7 < 8
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The answer is 7.  U, T% }! O( Q' k

1 c5 J( d" q5 Q4 l6 s( J9 N6 ze.g. #3 假設13為較輕的一粒
6 x3 @2 O8 K' v- x. PRound 1
2 Q$ l$ J! e6 g9 c1,2,3,4 vs 5,6,7,8 = equal# U, I5 O3 g" e* X0 I
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Round 2! X3 B2 X: Z5 I8 |5 x+ a
9,10 vs 11,12 = equal$ [9 I2 G4 G, q$ B7 c# T
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No Round 3
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The answer is 13.
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唔知我答得正唔正確呢?!
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4 K0 s$ e9 ]  r# G. [1 t[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]