hello1997

分3組4隻波子秤
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Group A: 1,2,3,4
! s9 G5 ~4 m: }$ T3 ^Group B: 5,6,7,8
. E' ?+ i  n/ |; m' JGroup C: 9,10,11,12
7 Q: F8 @  `, w2 h# [% g* OGroup D: 13
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6 O7 Q, a  c9 O! j' DRound 1
# H! e7 P0 J- c% _/ KGroup A vs Group B, y0 O# ^2 n! {; F
如A and B一樣, 即較輕一粒在Group C or D
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8 J3 g; N1 |) y8 ^" K! }! MRound 2+ K- `- B5 f1 W# q4 f
再在Group C拆成:
0 x; }# N$ @4 r/ |Group Ca: 9,10( h) k8 S( x5 Q$ N5 J. d
Group Cb: 11,12
0 j& U9 ?- ^2 R然後再秤, 如一樣, 即13為較輕一粒.% g; V& }* a& O! M( n, ~5 [$ M) Y

* H0 o  ?! `3 d* y5 D- X如不同, 即較輕一組有一粒較輕波子在其中,
/ V" T& Q. i& o+ H* m' o" R9 M要再秤, Round 3, 之後便知答案.
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4 T9 _& v. m/ }- d2 O  k- [e.g. #1 假設10為較輕的一粒3 u5 s" Z2 ]& z& p, c/ g6 s- W
Round 1& ~% r- g, N0 g  |  [- y
1,2,3,4 vs 5,6,7,8 = equal) H) C: j; b" U* X; k4 n0 P* M# q
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Round 2
( K: Y0 T1 w* S0 g$ g9,10 vs 11,12 = 9,10 < 11,122 T, v) C! ?/ W

( t' Y) [9 K# I. E4 S' w0 @Round 3' X+ s& c* i3 ]1 M! V! h; i
9 vs 10 = 9 > 10
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- C4 K0 o; B$ D6 X: }The answer is 10.: _( z' ?0 ~: f  V6 C3 Q9 |! @0 `

7 V1 ~9 {) _) c- \2 z) We.g. #2 假設7為較輕的一粒
  `% F7 B1 T  m, g" z4 F. L2 s) jRound 1
  ]0 p* {3 E! z" c1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,8- o  a# F8 |) s, j! f
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Round 2
! ]! F2 A5 H5 z' U# i! k. Y5,6 vs 7,8 = 5,6 > 7,8
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% @" U4 u7 @" X! [2 F: Q, @Round 3
' Z% g2 Y7 n+ l8 M7 vs 8 = 7 < 8+ @: H0 {) M  R2 i7 Z* t3 ]
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The answer is 7.8 y1 g/ [7 m, z. ~2 ?% F2 E
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e.g. #3 假設13為較輕的一粒
; o3 g* j8 ]% @* f2 u2 K% bRound 1
8 {1 [* q) h1 I$ L0 @. x1,2,3,4 vs 5,6,7,8 = equal2 Y7 g3 G& t) @8 V! D& z5 V' j( I
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Round 2* b& v/ }. n- {5 |" G2 c4 j
9,10 vs 11,12 = equal
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" W; C$ v4 w2 Z& B$ A' n0 {No Round 3
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The answer is 13.; @( B3 U. \# y4 }  {
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唔知我答得正唔正確呢?!
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- L/ n# v$ \+ O2 ~" b4 @/ S[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]