hello1997

分3組4隻波子秤
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Group A: 1,2,3,48 }8 m% B% k3 L6 _8 j4 m
Group B: 5,6,7,8
! U- x; ^3 ]0 c$ z+ `2 tGroup C: 9,10,11,12
6 {% h$ A# P& ?! `5 k- sGroup D: 13* a, [7 ~( ^4 B+ h* S9 z

/ T  w$ l( A8 D) e( G2 ]+ ZRound 1
: w( J. E, ^/ [1 Y$ D; s$ RGroup A vs Group B: p. }( Q9 H  R) v3 u- V+ P
如A and B一樣, 即較輕一粒在Group C or D
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1 m" g1 w, }$ J; S. l0 W( WRound 27 w7 U9 s$ m- ?- Y( v
再在Group C拆成:9 G- f2 e/ Z" X0 O4 X0 g; d
Group Ca: 9,10
" B7 X$ f0 A: K# m& I' H, MGroup Cb: 11,12) A! r: q! ^7 @0 k+ G0 p$ y/ }
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, ! \) y; N4 z& X4 k* ^9 [2 s, C
要再秤, Round 3, 之後便知答案.! x# ^* d. Y5 f; n, u* y
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e.g. #1 假設10為較輕的一粒- `* a. M! B/ ]1 R' H: M9 P
Round 1
2 V" e2 G$ Z, _2 `1,2,3,4 vs 5,6,7,8 = equal
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4 q) Z7 W  `+ h5 K. bRound 2( G% ^$ s" t/ J$ \( b
9,10 vs 11,12 = 9,10 < 11,12+ A3 o. `" I" T4 b2 N! c

+ a- u" q" B* c. O) uRound 3' i7 y6 `& `8 u! |$ \/ B
9 vs 10 = 9 > 10
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The answer is 10.
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0 S; S- U" M& h" j3 Ne.g. #2 假設7為較輕的一粒0 d3 [8 \; N6 ~
Round 1! ]3 ^9 h; U8 F3 q) t# ]8 a. H
1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,8
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Round 2) N( @& a5 `0 T
5,6 vs 7,8 = 5,6 > 7,83 L, L. O5 p0 z4 ]

) r" m+ ~8 S+ S4 H* WRound 3
" @, C" G' ^0 @2 B7 vs 8 = 7 < 8
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The answer is 7.
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e.g. #3 假設13為較輕的一粒
! W* T4 N" w( a( L9 S  C; zRound 1
- O* H- t+ l2 |% f% k2 G. Q% m7 D1,2,3,4 vs 5,6,7,8 = equal
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9 X, z' Z7 K2 A- S3 A" Q$ `9 k# qRound 23 y7 I( d" B% u
9,10 vs 11,12 = equal/ I/ X. L6 V( q* z0 `, C

4 C- Z' T$ C# }! G$ R3 [0 a8 QNo Round 3* @9 f5 N( ?$ S+ z& T9 N

6 K# s: N9 i2 }# _) i9 f* lThe answer is 13.  t! A  u  [. t/ a$ a& V' N! D
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唔知我答得正唔正確呢?! 1 D$ J6 G9 P. I* _, I, J. h- ?
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[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]