SDCAR2010【游戏入门】64-2 解析

sdcar2010

64-2
党中央需要派党代表去三个公司：Verizon, Yahoo，和 Zillow。五个党代表候选人是：James, Keven, Liang, Nemo, 和 Ostrich。每个公司有一个党代表。没有任何党代表被派到一个以上的公司。派遣细则是：
Either Keven or Nemo, but not both, 被任命为党代表。
如果 James 去当党代表，那么 Keven 也得当。
如果 Ostrich 去 Verizon 当党代表，那么 Keven 不能去 Yahoo 当党代表。
如果 Liang 去当党代表，那家公司是 Zillow 。

Analysis:
The original English version of this problem is a good test for your reading comprehension. As usual, the key to solve the question is to clearly understand the rules.

First, this is a hybrid game of grouping: in-and-out type coupled with matching type. We have one and ONLY one open seat for each of the three companies: V, Y, and Z. The five candidates are J, K, L, N, and O. One of K or N HAS to be chosen. J-->K. If O matches with V, then K does not match with Y. L HAS to be in Z, if chosen. The final diagram can be found in the following picture:

SDCAR2010 【游戏入门】64-1 解析
SDCAR2010【游戏入门】64-3 解析

sdcar2010

7) Which one of the following could be the assignment?

A) V: J; Y: O; Z: N
B) V: K; Y: J; Z: L
C) V: L; Y: N; Z: O
D) V: N; Y: J; Z: K
E) V: O; Y: K; Z: L

8) The pair of candidates who are not assigned as 党代表 could be

A) J & N
B) J & O
C) K & L
D) K & N
E) L & O

9) If Ostrich is assigned as 党代表 to Verizon, then the other two 党代表 could be

A) J & L
B) J & N
C) K & L
D) K & N
E) L & N

10) If Kevin i s assinged as 党代表 to Yahoo, which one of the following must be true?

A) J to V
B) L to Z
C) O to Z
D) J is not 党代表
E) O is not 党代表

11) Which one of the following CANNOT be true?

A) J to Z
B) K to Z
C) N to Z
D) L is not 党代表
E) O is not 党代表

12) Which one of the following, is substituted for the constraints that 如果 James 去当党代表，那么 Keven 也得当,  would have the same effect in determing the assignment?

A) If Kevin is assigned to 党代表, so is James.
B) If Liang and Ostrich are both assigned to 党代表, then so is Nemo.
C) If Ostrich is not assigned to 党代表, then Kevin is assigned to 党代表.
D) James and Nemo are not both assigned to 党代表.
E) Nemo and Ostrich are not both assigned to 党代表.

HarrisZheng

7  use + to stand for assigned , - for not assigned
A J+ K- out
C L=V our
D K+ N+ out
E O=V and K=Y out
thus B

HarrisZheng

8
if K- then J-
so choices CD out
if J+ then K+ and N- so E out
K and N can not be both + so B out
thus A

HarrisZheng

9

if J+ then K+ and N- so AB out
K and N can not be both +  so D out
If K&L both + then O=V L=Z K=Y  so C out
thus E

HarrisZheng

10
If K=Y then O≠V and N-
If L+ then K=Y L=Z O≠V  J=V ,
If L- then K=Y O=Z J=V
so in each case, J always =V
thus A

HarrisZheng

11
A If J=Z then K+ L- N- , can be true for now
B If K=Z then N- L-, can be true  for now
C If N=Z the K-, J-,L- can not have 3- ,
so C

HarrisZheng

12
which condition will allow K- lead to J-
A out
B if K- then N+ , does not lead to J- ,out
C if K- then N+ O+ , does not lead to J-, out
D if K- then N+ J-, bingo
E if K- then N+ O- J+, out

Notice that: James and Nemo are not both assigned ≠ Either  James or Nemo is assigned, but not both .
It can be this: both J and N are not assigned.

HarrisZheng

quite time consuming, I guess I am not familiar with these kinds of questions at all.

sdcar2010

Another way to solve this question:

If O in V, then K is NOT in Y.
If K is IN, then K must be in Z. So L is out, together with N. That gives us K & O in. Unfortunately, that is not one of the choices. So K is out, and N is in.

If N is in and N is in Z, than both K and L are out. That gives us N &O in. Unfortunately that is not one of choices.

If N is in and N is in Y, then both L and O can be in Z. That makes Z the correct answer.

9

if J+ then K+ and N- so AB out
K and N can not be both +  so D out
If K&L both + then O=V L=Z K=Y  so C out
thus E

-- by 会员 HarrisZheng (2011/12/12 17:34:47)