You are locked inside a room with 6 doors - A, B, C, D, E, F. Out of which 3 are Entrances only and 3 are Exits only. One person came in through door F and two minutes later second person came in through door A. He said, "You will be set free, if you pass through all 6 doors, each door once only and in correct order. Also, door A must be followed by door B or E, door B by C or E, door C by D or F, door D by A or F, door E by B or D and door F by C or D." After saying that they both left through door B and unlocked all doors. In which order must you pass through the doors?
(A) CFDAEB (B) EFDABC (C) BFDACE (D) CFDABE

• Find the doors as entry or exits..
  Entry doors-- A, E, F ; rest exit doors.
  The answer will be D Check the constraints that are on the following doors.
• 12 years agoHelpfull: Yes(23) No(3)
• It is given that one person came in through door F and second person came in through door A. It means that door A and door F are Entrances. Also, they both left through door B. Hence, door B is Exit.
  
  As Exit and Entrance should alter each other and we know two Entrances, let's assume that the third Entrance is W. Thus, there are 6 possibilities with "_" indicating Exit.
  
  
  
  1) _W_A_F (2) _W_F_A (3) _F_W_A (4) _F_A_W (5) _A_W_F (6) _A_F_W
  
  As door A must be followed by door B or E and none of them lead to the door F, (1) and (6) are not possible.
  
  Also, door D must be the Exit as only door D leads to the door A and door A is the Entrance.
  
  (2) _W_FDA (3) _F_WDA (4) _FDA_W (5) DA_W_F
  
  Only door D and door C lead to the door F. But door D is used. Hence, door C must be the Exit and precede door F. Also, the third Exit is B and the W must be door E.
  
  (2) BECFDA (3) CFBEDA (4) CFDABE (5) DACEBF
  
  But only door B leads to the door C and both are Exits. Hence, (2) and (5) are not possible. Also, door F does not lead to door B - discard (3). Hence, the possible order is (4) i.e. CFDABE.
  
  
• 12 years agoHelpfull: Yes(10) No(1)
• ans. is A. CFDAEB going through the option
• 12 years agoHelpfull: Yes(9) No(6)
• ans seems to be A & D both
• 12 years agoHelpfull: Yes(3) No(5)
• @anubhav : how can u say that e is an exit door?it is not given in the question.
• 12 years agoHelpfull: Yes(2) No(0)
• between a and d,the correct answer is "a" because we do not know whether e is a exit door or entry door in option d
• 12 years agoHelpfull: Yes(2) No(0)
• a&d both is the ans
  
• 12 years agoHelpfull: Yes(1) No(3)
• Ans:B;
  E,D,B are exit doors F,A,C are entrances
• 12 years agoHelpfull: Yes(1) No(6)
• a is the answer
• 12 years agoHelpfull: Yes(1) No(0)
• by option study two options are favorable A and D which are following the sequence
  but A wrong coz according 2 Question b is exit door but in A b is an entrance door ( consider that currently m inside the room so the sequence will start with exit door)
  D is correct ans
  
• 12 years agoHelpfull: Yes(1) No(0)
• pls give the answer mail is shyamleshd@gmail.com
• 12 years agoHelpfull: Yes(0) No(5)