Question

Directions:- Study the following information carefully to answer the question given below.

Five persons A, B, C, D and E are either guards or thieves.The guards always tell the truth whereas thieves always tell a lie. A claims that B is a guard. B claims that C is a thief. C claims that D is a thief. E claims that A is a guard. D claims that B and E are different kinds. What is the number of thieves?

• A. 1
• B. 2
• C. 3
• D. 4
• E. Inadequate data

Answer 1

The correct option is D 4

Condition (1):-
Let A be the thief. Now according to the conditions:-
A claims that B is a guard $\Rightarrow$ B is a thief
B claims that C is a thief $\Rightarrow$ C is a guard
C claims that D is a thief $\Rightarrow$ D is a thief
D claims that B and E are different kinds $\Rightarrow$ B and E are of the same kind
There E should he a thief.

Condition (2):- Now, let A be the guard,
A claims that B is a guard. It is true.
B claims that C is a thief. It is also true.
C claims that D is a thief. D is a guard.
E claims that A is a guard. It is true. Hence, E is a guard. B and E are guards. It contradicts the given condition as none, B or D tells a lie.
Clearly, condition (1) is applied here and
A - Thief
B - Thief
C - Guard
D - Thief
E - Thief
Hence, the required answer is (D)