hello1997

分3組4隻波子秤
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& p5 z" q% D  HGroup A: 1,2,3,4! o, I& E9 u6 V, l/ C- q2 W" a) p; z2 B
Group B: 5,6,7,8
, @8 }: Q  {, Q! B/ C; OGroup C: 9,10,11,12* f) H+ H# n) V, F! p  I+ v
Group D: 13
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' C* D' _6 d# X2 PRound 19 {" {- o6 }* z; V0 h1 N
Group A vs Group B
- \- W; s) m/ W. [3 F如A and B一樣, 即較輕一粒在Group C or D1 M& T5 |" g0 n' }% h  b
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Round 2
$ [9 Y; ]. x7 h! K再在Group C拆成:- d( L/ V. D0 o; n4 ?! l# R) _
Group Ca: 9,10/ I& n/ a* u7 d6 ^6 z' g1 g  c; e* f# D
Group Cb: 11,12
1 {; M, p- O( J! O* K然後再秤, 如一樣, 即13為較輕一粒.& c# E. w; M$ J( P
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如不同, 即較輕一組有一粒較輕波子在其中, 5 C4 \9 u4 q: p  m6 m( [$ [% S9 I
要再秤, Round 3, 之後便知答案.! q4 a0 S; j' T; ]. g7 `- H

2 n4 \. z3 Y! {9 e+ N) s2 Ne.g. #1 假設10為較輕的一粒& u, E/ ^; g: c
Round 1
  f9 ^% J0 x8 }3 [( f1,2,3,4 vs 5,6,7,8 = equal& q! Z! u( _& Q

* D0 _1 y9 L& V3 }7 A$ HRound 2
) S% {3 z. }) _& D- g( G; \) B9,10 vs 11,12 = 9,10 < 11,12. L# D- A# o& f5 K; ~
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Round 3: ]' y2 [2 O( F
9 vs 10 = 9 > 10
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The answer is 10.2 m/ W7 R! t- Q

5 C! y2 E' |/ [  v- oe.g. #2 假設7為較輕的一粒
% c, D! n, o$ _8 \* F5 s- b6 xRound 1% \7 p( _5 ?, v2 ~0 w
1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,82 B6 w/ i, f" }

. F2 H4 s+ w- `; k) `- [6 t. G7 LRound 2* K% z9 R) L- o) @1 |0 _" e, _
5,6 vs 7,8 = 5,6 > 7,8$ F" B% e* E- c# ~
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Round 3. P9 ]* l) ~* p8 ]4 @
7 vs 8 = 7 < 8, f" A. l5 [6 E3 {, Z5 W, ]8 u4 x) J
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The answer is 7.4 ^, l  m9 N' d

- K: P% D/ H. @% V/ Ve.g. #3 假設13為較輕的一粒
$ ?" B) G1 a/ [$ m$ ]) |1 a" e* mRound 1  _3 V8 _8 N" o3 U: N
1,2,3,4 vs 5,6,7,8 = equal
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Round 2
# u+ s0 @+ ]: F; h" l* [9,10 vs 11,12 = equal) Q$ A3 v9 ~0 B  n3 m3 @4 {

  j+ F5 \' F  e9 yNo Round 38 }% U! s) C2 X: W5 O
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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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[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]