LSAT 逻辑游戏题（2）

sdcar2010

Jandra is a travel guide writer who will visit 7 countries: Australia, Bahrain, China, Djibouti, England, Fiji, and Guatemala. She must visit each of these countries in accordance with the following restrictions:

Jandra must visit exactly two countries before her visit to China but after her visit to Bahrain.
China cannot be the last country she visits.
Jandra cannot visit Bahrain until she has visited Australia.
She cannot visit England immediately after she visits Djibouti, nor can she visit Djibouti immediately after she visits England.
Fiji must be visited either 4th or 5th.

1. Which one of the following could be the order in which Jandra visits the countries, from first to last?

(A) Australia, England, Bahrain, Guatemala, Fiji, China, Djibouti
(B) Australia, Bahrain, Guatemala, Fiji, China, Djibouti, England
(C) England, Australia, Bahrain, Fiji, China, Djibouti, Guatemala
(D) Australia, Djibouti, Bahrain, Fiji, England, China, Djibouti
(E) Djibouti, Guatemala, Australia, Bahrain, Fiji, England, China


2. If Jandra visits China fifth, each of the following could be true EXCEPT:

(A) The second country she visits is Bahrain.
(B) The third country she visits is Guatemala.
(C) The third country she visits is Djibouti.
(D) The sixth country she visits is England.
(E) The seventh country she visits is Djibouti.


3. If Jandra visits Djibouti second, but she does not visit Fiji fourth, each of the following could be true EXCEPT:

(A) She visits Guatemala immediately before she visits Fiji.
(B) She visits Guatemala immediately after she visits China.
(C) She visits Bahrain immediately before she visits Guatemala.
(D) She visits Fiji immediately before she visits Guatemala.
(E) She visits Fiji immediately after she visits England.


4. If Jandra visits Australia and Bahrain first and second on her trip, respectively, how many different orders are there in which she can visit the seven countries?

(A) one
(B) two
(C) three
(D) four
(E) five


5. If the condition that China cannot be visited last is removed, and Jandra takes advantage of the opportunity to visit China last, but all other conditions remain in effect, which one of the following could now be a complete list of countries, any one of which could be visited third?

(A) Australia, Djibouti, Guatemala
(B) Djibouti, England, Guatemala
(C) Australia, Djibouti, England, Guatemala
(D) Australia, England, Fiji, Guatemala
(E) Australia, Bahrain, England, Guatemala

taoransk

7 countries: ABCDEFG

B - ? - ? - C
C =/= 7
A < B
No (DE)/(ED)
F = 4/5

Diagram:

A < (B - ? - ? < C)  So C = 5/6

If C = 5,
-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

If C = 6,
-(A&?)--B--(F&?)--C--?
-1--2--3--4--5--6--7


1. Which one of the following could be the order in which Jandra visits the countries, from first to last?

(B) ED together
(C) Only 1 between B & C
(D) D * 2
(E) C = 7

Answer : (A)


2. If Jandra visits China fifth, each of the following could be true EXCEPT:

-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

Answer : (B)


3. If Jandra visits Djibouti second, but she does not visit Fiji fourth, each of the following could be true EXCEPT:

-A--D--B-G/E-F--C-E/G
-1--2--3--4--5--6--7

Answer : (D)


4. If Jandra visits Australia and Bahrain first and second on her trip, respectively, how many different orders are there in which she can visit the seven countries?

-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

Orders: ABDFCEG ABDFCGE ABEFCDG ABEFCGD

Answer : (D)


5. If the condition that China cannot be visited last is removed, and Jandra takes advantage of the opportunity to visit China last, but all other conditions remain in effect, which one of the following could now be a complete list of countries, any one of which could be visited third?

C can be 7, then If C = 7,
-?--?--?---B--F--?--C
-1--2--3--4--5--6--7
(E/D-A-D/E)------G
-(A+E/D+G)-----D/E

3 = A/D/E/G

Answer : (C)

sdcar2010

Bravo.  Your answers are perfect.  So are your diagrams.

7 countries: ABCDEFG

B - ? - ? - C
C =/= 7
A < B
No (DE)/(ED)
F = 4/5

Diagram:

A < (B - ? - ? < C)  So C = 5/6

If C = 5,
-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

If C = 6,
-(A&?)--B--(F&?)--C--?
-1--2--3--4--5--6--7


1. Which one of the following could be the order in which Jandra visits the countries, from first to last?

(B) ED together
(C) Only 1 between B & C
(D) D * 2
(E) C = 7

Answer : (A)


2. If Jandra visits China fifth, each of the following could be true EXCEPT:

-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

Answer : (B)


3. If Jandra visits Djibouti second, but she does not visit Fiji fourth, each of the following could be true EXCEPT:

-A--D--B-G/E-F--C-E/G
-1--2--3--4--5--6--7

Answer : (D)


4. If Jandra visits Australia and Bahrain first and second on her trip, respectively, how many different orders are there in which she can visit the seven countries?

-A--B-D/E-F--C-(E/D&G)
-1--2--3--4--5--6--7

Orders: ABDFCEG ABDFCGE ABEFCDG ABEFCGD

Answer : (D)


5. If the condition that China cannot be visited last is removed, and Jandra takes advantage of the opportunity to visit China last, but all other conditions remain in effect, which one of the following could now be a complete list of countries, any one of which could be visited third?

C can be 7, then If C = 7,
-?--?--?---B--F--?--C
-1--2--3--4--5--6--7
(E/D-A-D/E)------G
-(A+E/D+G)-----D/E

3 = A/D/E/G

Answer : (C)

-- by 会员 taoransk (2010/11/7 12:07:19)

baileys2010

第一题的选项d也满足要求。

解题方程里面的条件是A>B 而不是A<B

sdcar2010

第一题的选项d也满足要求。

解题方程里面的条件是A>B 而不是A<B

-- by 会员 baileys2010 (2011/1/14 14:52:49)

You misundertood the following condition:
Jandra cannot visit Bahrain until she has visited Australia.

You need to be crystal clear about the UNTIL/UNLESS/WITHOUT/EXCEPT clause in the LSAT games.

A quick way to translate these clauses is the following:
1) Take any of these words (UNTIL/UNLESS/WITHOUT/EXCEPT ) as introducing the necessary condition. To put it another way, whatever statement immediately follows one of these words is your NECESSARY condition of the statement.

2) Negate whatever other clause left in the same statement ans you will have the sufficient condition for the statement.

Using the above method, you get: If B, then already A. Or A is ahead of B.