Dear Reader, Below I will post three logical questions. Some questions require assumptions to start with while others require pure logical application.
Question 1
Mr. Kohli had a doubt regarding a situation and he approached Mahendra for clarification. The question read as under:--
One of four people –two men Raman and Krishnan and two women, Sonam and Kala -- were murdered.
Hint : Raman's sister is Krishnan's wife and vice versa.
1) Raman’s sister argued exactly once with Sonam’s legal husband after the murder.
2) Krishnan’s sister argued twice with the victim’s legal spouse after the murder.
Help Mahendran identifying the victim?
a) Krishnan b) Raman c) Sonam d) none of these.
Answer : a) Krishnan.
Solution :
1) Raman’s sister argued exactly once with Sonam’s legal husband after the murder.
2) Krishnan’s sister argued twice with the victim’s legal spouse after the murder.
From both the statements, we can see that the victim has to be a MAN as both the sisters were involved in arguments after the murder.
To solve such problems, we will have to assume a Victim and check the possibility of all statements. If even one of the statements is logically impossible then our nearest assumption would be false.
1) Assume Raman is the victim.
1a) Assume Raman's Sister is Kala
(If Raman's Sister is Kala then Krishnan's sister has to be Sonam. Also Raman's wife has to be Sonam and Krishnan's wife has to be Kala.)
As per statement I, Kala would had argued with Raman after the murder. – Impossible. (But since we have assume Raman is the victim this is not possible.)
1b) Assume Raman's Sister is Sonam
(If Raman's Sister is Sonam, then Krishnan's Sister would be Kala, Raman's Wife would be Kala and Krishnan's wife would be Sonam)
As per statement I, Sonam would had argued with Krishnan after the murder. - Possible
As per statement II, Kala would had argued with Kala after the murder.- Impossible. (Kala cannot argue with herself)
2) Assume Krishnan is the victim.
2a) Assume Raman's Sister is Kala
(If Raman's Sister is Kala then Krishnan's sister has to be Sonam. Also Raman's wife has to be Sonam and Krishnan's wife has to be Kala.)
As per statement I, Kala would had argued with Raman after the murder. - Possible
As per statement II, Sonam would had argued twice with Kala after the murder. – Possible
All the statement hold good if Krishnan is the Victim provided Raman’s sister is Kala.
2b) Assume Raman's Sister is Sonam
(If Raman's Sister is Sonam, then Krishnan's Sister would be Kala, Raman's Wife would be Kala and Krishnan's wife would be Sonam)
As per statement I, Sonam would had argued with Krishnan after the murder. – Impossible (as we have assumed Krishnan is the victim)
Question 2
Consider the below statements. One of the friends is lying while others are saying the truth. Find the person who is lying.
1) Ram says he is taller than both Ravi and Rahul
2) Raju says he is not taller than Ram and Ravi
3) Rahul says he is taller than Rajan and also adds he is neither taller nor shorter than Ravi
4) Rajan says he is taller than Ram
5) Ravi says he is taller than Rajan
a) Ravi b) Rajan c) Ram d) Rahul e) Raju
Answer : b) Rajan
Solution :
Based on the statements given, let us start arranging the people in order of their heights.
As per statement 1, Ram is taller than both Ravi and Rahul. Also from second part of statement 3, we can easily say that Rahul is equal in height to that of Ravi.
Arrangement : Ram, Ravi, Rahul
As per statement 2, Raju is shorter than both Ram and Ravi
Arrangement : Ram, Ravi, Rahul, Raju
As per statement 3, Rahul is taller than Rajan
Arrangement: Ram, Ravi, Rahul, Rajan, Raju (as of now we will assume Rajan is taller than Raju)
As per statement 4, Rajan is taller than Ram,
Here is the catch! Rajan is clearly shorter than Ram from statements 1 and 3. Now if we assume Rajan is speaking the truth then we will have to conclude both Ram and Rahul are lying. But the question clearly says only one of the friends is lying. Hence statement 4 is false and Rajan is lying.
(Additional Information : As a matter of fact, Ravi is also saying truth as his statement perfectly falls in line with the arrangement we made so far...)
Question 3
Consider four brothers A,B,C,D. A is the eldest of all.
The immediately younger brother to A always plays with the youngest brother among all four.
D is the immediately elder brother to the youngest brother.
Find the brother who is immediately younger to A.
a) B b) C c) either B or C d) can’t be determined
Answer : c) either B or C
Solution :
It is given that A is the eldest of all and D is immediately elder to the youngest brother.
Hence one among B and C has to be the youngest and the other one has to be immediately younger to A. But data in question is insufficient to arrive at the right person amongst B and C.