FIRST correct answer 10 points ! logic?

Question

You are an expert on paranormal activity and have been hired to locate a spirit haunting an old resort hotel. Strong signs indicate that the spirit lies behind one of four doors. The inscriptions on each door read as follows:

Door A: It's behind B or C

Door B: It's behind A or D

Door C: It's in here

Door D: It's not in here

Your psychic powers have told you three of the inscriptions are false, and one is true. Behind which door will you find the spirit?

Answer 1

well it reads the same four writings on all four doors,because u said the inscription on each door reads etc etc.so it,s not in any door or theres four doors to the same room.

Answer 2

D?

Answer 3

if the second statement is true. then it isn NOT behind B

if all other are false then it CANNOT be behind door C

Doors A's statemen can be false with out the ghost being in door A

If door D's statement is false then it must be behind door D which hold true to statment B

Ghost is at Door D

Answer 4

The inscriptions on doors A and B cannot both be false. One of them must be true.

Since there's only one true inscription, and the true one is either A or B, we know that C and D are definitely both false.

Since C is false, we know the spirit is not behind Door C.

Since D is false, we know the spirit IS behind Door D. (SOLUTION)

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To spell it out,

Suppose A is true.

...Then, the spirit is behind B or C.

...C is false, so the spirit is not behind C

...D is false, so the spirit is behind D.

...However, Door A, which is supposed to be true, states that the spirit is behind B or C, not D,

Therefore, Door A must be false.

Suppose Door B is true.

...Then, the spirit must be behind A or D

...Door C is false, so the spirit must not be behind C

...Door D is false, so the spirit must be behind D.

Therefore, Door B is true, and the spirit is behind Door D.

Answer 5

Suppose that the answer is door D.  Then, in order, the labels are:

A: false.

B. true

C. false

D. false.

Counting noses, this meets the requirements.

Answer 6

D

Answer 7

if a is true, b is false, c is unknown and d is true

if b is true,  a is false, c is false and d is unknown

if c is true, a is true, b is false, d is true

if d is true, a is unknown, b is false, c is false

B or d is true.  if b is true, so is d so, it must be D

Answer 8

The spirit lies behind Door D.

If the spirit is behind Door A, then both B and D are true.

If the spirit is behind Door B, then both A and D are true.

If the spirit is behind Door C, then A, C, and D are all true.

If the spirit is behind Door D, then the statements on all the doors are false, except for that on Door B. This matches the rules, and therefore, the resort hotel spirit lurks behind Door D.

Answer 9

If door A is false, then the spirit is not in B or C

If door B is true, then the spirit is in A or D

If door C is false, then the spirit is not in C

If door D is false, then the spirit is in door D

Answer 10

Door B is true, so it's in door D.

Answer 11

The answer is Door D.

As for the reason,Simple,Assuming the statement of D is correct:-

Statement of A is false. Thus the spirit is not behind B or C.

Statement of B is false. Thus it is not behind A or D.

Statement of C is is false. Implying it is not behind C.

Statement of D is correct. Thus it is not behind D.

Therefore,if we sum it all up,it appears that the spirit is  behind none of the doors,contradicting to the statement of the riddle(The spirit must be behind one door). So D can't be correct. D states that the spirit is not behind the door D. Thus the spirit is in Door D.

Thus the answer,Door D. :)

Answer 12

Door D

Answer 13

Door C

Answer 14

Door B

Answer 15

Not door A

Not door B

Not door C

It's behind door D.  That way Door A's message is false.  Door B's message is true.  Door C's message is false.  Door D's message is false.  That's 3 falses and one true.