hello1997

分3組4隻波子秤
* Z- Q+ X" V! C3 z2 t1 G6 P7 g1 [/ R- Q7 Q$ Q
Group A: 1,2,3,4
4 r& ~7 ]2 }9 B5 h/ hGroup B: 5,6,7,8
6 p! I( S* I8 e/ G! U1 wGroup C: 9,10,11,12  ]" k4 {0 ]* [3 c
Group D: 13
: Y! e/ {4 p9 o. }" ^3 P
2 S- v' ^4 Q: CRound 1( X% ]8 V4 v$ E( O  h7 k7 I- R
Group A vs Group B: Q! c5 ~/ S7 z* {4 f4 \0 K
如A and B一樣, 即較輕一粒在Group C or D) s9 }: F6 {8 ?9 a6 f
- p' D- T0 U) o- p$ p
Round 2: `2 y" F& `1 V2 P* q+ c  g
再在Group C拆成:) G$ ~, s4 O! ~3 _: b2 B* h1 P
Group Ca: 9,104 ~+ ]6 F' |- _) L- R. `2 v. o2 t
Group Cb: 11,12
$ g' ~8 W9 o, |* E6 f然後再秤, 如一樣, 即13為較輕一粒.
; W' J8 c& C& x+ I
( T/ [9 x- l5 z5 p; y, l3 w% O. Q2 G如不同, 即較輕一組有一粒較輕波子在其中,
% q7 Y0 A1 a8 y( m; M6 ~( Z1 \要再秤, Round 3, 之後便知答案.8 C2 z/ \1 z5 G3 l: E4 T; @

9 Y  W5 q4 [8 f8 w# |e.g. #1 假設10為較輕的一粒7 R0 [! m9 v5 |  W; |
Round 1* ~7 @; q1 a) }2 M; P" Z  ?
1,2,3,4 vs 5,6,7,8 = equal% \- @/ U) {* `
- v% T: b7 }* v7 |' o$ q, @
Round 2
9 I$ x9 L& E# r/ \& t1 K9,10 vs 11,12 = 9,10 < 11,12/ y$ z; X5 k6 a/ C0 }

& ~7 H) I4 i- QRound 35 |4 d, p% c5 P* l, _  w' C. B0 T
9 vs 10 = 9 > 10
5 o# [! e* R9 Y
' L$ p/ ]' S- l* g$ K# bThe answer is 10.
+ H! M* U; X% Y0 k
* K3 h- W5 [0 ~0 Y4 p$ `; J3 Je.g. #2 假設7為較輕的一粒* G' e3 c3 ~5 g! F, Z
Round 11 ^9 j# `4 f6 d2 T! z0 a3 ~
1,2,3,4 vs 5,6,7,8 = 1,2,3,4 > 5,6,7,8
: G) D, Z4 ^9 ?3 n8 _
; h" N* R+ M  YRound 2
0 D" m3 B3 ?3 g5,6 vs 7,8 = 5,6 > 7,83 Q1 y  w# C" a( O
6 L% |# v3 [; I; _. ?9 G
Round 30 D0 J' o  m% {  _! A
7 vs 8 = 7 < 8
% X: `& f2 k2 ^/ [$ b0 U- L  u; ^) h/ @7 Z* W/ y7 Z, Z- H/ `9 w
The answer is 7.; N2 n2 j3 C' K8 X$ \  W1 @
' `: O1 I6 D+ M) A% J
e.g. #3 假設13為較輕的一粒
' e/ v& U: ]4 ~Round 1
1 H5 l# C$ x* e7 o* N' }1,2,3,4 vs 5,6,7,8 = equal! x8 B& f5 l; J( t. `

2 S& ~8 `, D( TRound 2
; c  h) g1 a2 m, m9,10 vs 11,12 = equal( g% l8 W7 C0 m

5 }# T4 g. E6 x) ?- ANo Round 30 f, [7 g0 A+ ?7 O  Y8 ^, s1 Y7 O

( b  i' ]4 {, `The answer is 13.
. |/ h+ A5 o* o0 x0 @7 f$ V& Y" b. \7 j, X. g- e
唔知我答得正唔正確呢?! ( P; t( S' L$ R- Y  H
/ Z) I4 Z! }  w4 u+ a0 o
[ Last edited by hello1997 on 2007-3-2 at 12:39 AM ]