hello1997

分3組4隻波子秤( c7 J* a) n6 Q( F3 ]* d# d

9 W$ T# g7 i( V  }- x. X; n" wGroup A: 1,2,3,4! i2 D2 I- y4 p3 T# Q
Group B: 5,6,7,89 |2 S6 }; e4 k' X
Group C: 9,10,11,12
/ U9 ?: E1 x$ R' ?6 E2 v! B0 @Group D: 13
7 G, C! i; ]2 m1 _2 S3 f# h+ M9 y, |7 w9 M7 e! J7 m9 y; ?
Round 1
! I. \% v, r+ ?8 h* ~6 o9 HGroup A vs Group B" p( E7 g5 O+ e
如A and B一樣, 即較輕一粒在Group C or D
% D& C7 t9 N6 n+ e9 i  _7 v1 O' O2 V* o
Round 2
$ Y) _4 _1 K0 A/ D9 y0 e5 z再在Group C拆成:
! `8 a" ]5 @, H8 P& ]; r! mGroup Ca: 9,10( D, {- B# `  x6 {( n9 j, \. Q
Group Cb: 11,12
# p# O1 j8 ?" Q& z然後再秤, 如一樣, 即13為較輕一粒.$ [: B9 a7 T( }2 k- M  l7 t3 E' ?
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如不同, 即較輕一組有一粒較輕波子在其中, & U, ]0 X. p+ E) {
要再秤, Round 3, 之後便知答案.
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e.g. #1 假設10為較輕的一粒
/ Z/ ~8 l, D0 L9 ERound 1
2 x2 R0 m) ?3 a- a% D4 ^0 |$ V3 i$ U6 r/ a1,2,3,4 vs 5,6,7,8 = equal
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2 U6 w* b8 H2 P# F  ERound 2+ b/ e2 f! r% v- j( w
9,10 vs 11,12 = 9,10 < 11,120 X5 k4 H4 H% v% K( }; X& y5 `2 J0 F

# F1 h7 ^( y! F. ]% M* C  I$ pRound 3
/ L5 h6 C) T4 O0 m9 vs 10 = 9 > 10( e( t" T$ @# X9 p6 E/ J% |6 u2 o1 ^

4 u  y! z& [( `9 Z( ?. _The answer is 10.$ u, i1 f; j. ?
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e.g. #2 假設7為較輕的一粒3 ?' ^; }1 _. t# v' l0 c1 \% l
Round 1
# w* P9 y; w9 y1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,8
) a# q* s4 s% g4 [2 D, C$ ?
5 ]  p7 u. Q+ r/ r" `Round 2/ R! a% P9 F- }4 v) |
5,6 vs 7,8 = 5,6 > 7,8& y& s* e, p( u/ F9 Z. {; q* N) o# G/ @
1 E. S6 k2 t" y4 ?( M+ D
Round 3
! L: R6 ]$ D7 q/ E+ q' [4 S7 vs 8 = 7 < 8
+ g4 f5 E% Q- k
0 l- u. p+ m4 X& r+ b9 \The answer is 7.
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e.g. #3 假設13為較輕的一粒
6 L0 x( p3 d; N5 s9 ]Round 1
9 I6 N$ e5 \  q, a% e. ?& i1,2,3,4 vs 5,6,7,8 = equal9 v& y) \0 n/ ~. j" i( e
6 m% G2 i! ~. l% ~+ c
Round 2
  g) d( ?% l0 q& V; d. `9,10 vs 11,12 = equal" h! t4 D  h7 F. _$ B

0 I' N1 b7 z- g3 pNo Round 3
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% }- T, A* p/ y7 X4 j% dThe answer is 13.' w3 {  p# Y7 P$ |* H
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唔知我答得正唔正確呢?! 1 s) y; J% L; M' I, Q
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[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]