hello1997

分3組4隻波子秤
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Group A: 1,2,3,45 d6 p: Q( I$ A
Group B: 5,6,7,8
& U2 {5 O4 q. _& t; B" iGroup C: 9,10,11,127 m7 B7 u3 X0 u4 }: U7 Y" h
Group D: 137 L) Z% N$ w2 `+ [7 F9 L$ c' r
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Round 1, O- q% f8 S! e7 K" ]& u& e& o
Group A vs Group B& t- Z  X" c' c: T% _
如A and B一樣, 即較輕一粒在Group C or D
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Round 2
( k6 r# g2 z! l0 o再在Group C拆成:- g% J9 j1 ]; I- o. |) G
Group Ca: 9,10, _" E0 ^7 D0 c
Group Cb: 11,12
5 E7 p' S) W+ G( Q5 Z3 J% y8 |然後再秤, 如一樣, 即13為較輕一粒.7 x- s1 [/ N( o6 z# D
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如不同, 即較輕一組有一粒較輕波子在其中,
3 K" P% E! {7 s要再秤, Round 3, 之後便知答案., V( u% R! _' w
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e.g. #1 假設10為較輕的一粒% ?: s  ?+ i  n2 \8 s
Round 1
) s$ B  @) c( e, s* m/ q( a' Y1,2,3,4 vs 5,6,7,8 = equal3 @  |+ }* d2 w
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Round 2' c9 }9 ~/ Z  W
9,10 vs 11,12 = 9,10 < 11,12
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3 V3 R' L8 D) c6 `6 uRound 3
6 j; |7 J; S8 A- d; n* v% W7 R9 vs 10 = 9 > 105 T; M5 [# ]. T: R" i

& h5 n# a% ?+ k7 AThe answer is 10., W0 z4 `! }$ v( x* j5 N

+ ~5 h8 D' _5 k0 r. U' fe.g. #2 假設7為較輕的一粒
# ~5 n& I( Q3 w9 x% fRound 1
/ j" Y0 w- U& n1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,8, P& @+ C1 U$ U/ ^& s
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Round 2
* W, {5 x/ X% u' R/ G% v9 y5,6 vs 7,8 = 5,6 > 7,84 W. S3 t" X3 b
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Round 3
8 p2 v, i( S0 l% j7 vs 8 = 7 < 8
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The answer is 7.+ G+ A  P3 u; x! l- ^5 A& n( k

1 ~1 P1 }# c( Y8 \3 Q7 oe.g. #3 假設13為較輕的一粒
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1,2,3,4 vs 5,6,7,8 = equal7 j  T. O, k5 @2 ]

# b1 P! J, Q# K8 \Round 2
0 Q7 Y. d+ R2 g( v* k0 g3 ]9,10 vs 11,12 = equal
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No Round 3
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The answer is 13.% ]. h; v( ~; D! P
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唔知我答得正唔正確呢?! + I: V2 q! P. C. ?( S  I

' [, G+ K  D# R: Q% |, E7 {0 \[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]