Binary Logic

Type - 1:
Direction On an island ‘Mola-Moola’ the inhabitants always answer any question with two sentences —one of which is always true and the other always false. Read the question below very carefully and choose the correct answer for the questions that follow: The commissioner of the island discovers that smuggling is rampant there . You have been hired as a private detective in order to determine the identity of the culprits and also to know more about the next heist on the basis of a plane. You question three suspects as to when the plane is expected and what it looks like. This is what they have to say: Subhash: It arrives at 11:00 p.m. The colour of the plane is only red. Rubhash: It arrives at 11:00 p.m. The colour of the plane is only yellow. Bibhash: I know at what time the ship arrives. Rubhash is lying about the time of arrival.



Ans .

b


  1. Explanation :

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Ans .

a


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Suddenly, a murder takes place on the island. It is imperative that you locate the person who is the murderer. On further investigation, you find that the murderer has to be a person who has been to the chief whip’s house within the last five days (today is Friday). By careful questioning, you narrow the possibilities down to three people. This is what they have to say.
Rani: ‘‘I went to the Chief Whip’s house. It was before Monday.”
Vani: “Rani did not go to the Chief Whip’s house. I have not gone to the Chief Whip’s house in the last five days either”.
Siwani: “Rani did not go to the Chief Whip’s house. I am not the murderer.”



Ans .

b


  1. Explanation :

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In the village of Rampur, all inhabitants always answer any question with two sentences, one of which is always true, the other is always false.
While visiting the village, Gauri meets three inhabitants—Rajesh, Mahesh and Ramesh near the village square. One of them is wearing a suit. Knowing that they were there to resolve a dispute over the ownership of some land, you ask them—“Who got the land?” They answer as follows:
Rajesh: “I got the land. Ramesh is wearing the suit.”
Mahesh: “I am wearing the suit. I got the land.”
Ramesh: “I got the land. I am not wearing the suit.”



Ans .

b


  1. Explanation :

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Ans .

a


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On waking up the next morning, you find that your brand new watch has been stolen. The suspects are the same trio you met the previous day. You question them (knowing that only one of them is guilty).
And they reply as follows:
Rajesh: “Mahesh did not do it. I did not do it.”
Mahesh: “I did not do it. Ramesh did not do it.”
Ramesh: “I did not do it. I do not know who did it.”



Ans .

b


  1. Explanation :

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In a small island called Neverneverland, the people always answer any question with two sentences —one of which is always right and the other is false.
Perhaps due to this peculiar habit, there’s been a high rate of suicides on the island. As a doctor, you have to identify potentially suicidal people and counsel them. You know that all people who are suicidal feel that life is futile. On questioning three inhabitants, these are the answers you get:
Anuj: “Himansu is suicidal. I am not suicidal.”
Himansu: “I do not want to die. Akshay does not want to die.”
Akshay: “Life is futile. I am suicidal.”



Ans .

a


  1. Explanation :

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Ans .

d


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Going around the village, you come across three people. One of them is a dentist, one a barrister and one a professor. You want to know who is who.
Peter says, ‘‘I am not a professor. Shina is not a professor.”
Matt says, ‘‘Peter is not a barrister. Shina is a professor.”
Shina says, ‘‘Peter is not a dentist. I am not a professor.”



Ans .

d


  1. Explanation :

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Further, you come across three women, one of whom is an excellent singer. You start questioning them, when you notice that Minaxi is wearing a flower in her hair.
Madhuri says, ‘‘I am not the singer. The singer wears a flower in her hair.”
Minaxi says, ‘‘I am the singer. The singer is amongst us.”
Jaya says, ‘‘Madhuri is the singer. Minaxi is not the singer.”



Ans .

c


  1. Explanation :

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You want to expand your horizons and decide to go to the village of “Where is Who”, which is further inside. You come to the border of “Kya Kya” and see a fork. One leads left and the other right. There are no other roads. You ask the inhabitants:
Maroof says, ‘‘I do not speak to strangers. I am new to these parts.”
Nafish says, “Take the road to the right. I am married to Ayesha.”
Ayesha says, “I am not Nafish’s wife. Maroof is not new to these parts.”



Ans .

a


  1. Explanation :

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On moving further, you come across another small village of Patina, whose inhabitants answer all questions with two sentences—one of which is true and the other always false.
I asked Shahrukh, Amitabh and Abhishek, “Did it snow last night?” and I got the following replies:
Shahrukh: Yes, it snowed last night. Moreover, Amitabh fell sick last night.
Amitabh: Yes, it snowed last night. But then I never lie.
Abhishek: No, it did not snow last night. But Shahrukh got married yesterday.



Ans .

c


  1. Explanation :

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Rophas Khopas is a small land locked country in the Vindhyanchal forest range, with a distinct dress, culture, food habits, national language, national dance, a national bird, and a national animal. The inhabitants speak in two sentences—one of which is true and the other false.
I asked Shiva, Monu and Vijay, the three important citizens of Rophas Khopas, “What is the national language of Rophas Khopas?” and I got the following replies:
Shiva: “French is our national language. Hundred percent of our citizens are literate.”
Monu: Latin is our national language. We have a very poor literacy rate in the country.
Vijay: We have a very poor literacy rate in the country. Our national language is Bhasha Khopas.



Ans .

a


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Ans .

a


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I asked Shiva, Monu and Vijay, “What is your national dress?” and I got the following replies: Shiva: Our national dress is Pathani suit. People wear the national dress on very special occasions only.
Monu: Our national dress is Sari. People wear the national dress on very special occasions only.
Vijay: Our national dress is suit boot. But no one is ever permitted to wear the national dress.



Ans .

c


  1. Explanation :

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I asked Shiva, Monu and Vijay, “What is your national food?” and I got the following replies:
Shiva: Our national food is sabudana khichdi. Most of our people are hale and hearty.
Monu: Our people are not hale and hearty at all. Our national food is makki ki roti.
Vijay: Most of our people are hale and hearty. Our national food is rice kee kheer.



Ans .

b


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Ans .

c


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I asked Shiva, Monu and Vijay, “What is your national bird?” and got the following replies:
Shiva: Our national bird is cackatoo. We are a peace loving country.
Monu. Our national bird is sparrow. We are a peace loving country.
Vijay: Our national bird is owl. But we worship the sparrow.



Ans .

d


  1. Explanation :

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I asked Shiva, Monu and Vijay, “What is your national animal?” and I got following replies:
Shiva: Our national bird is kangaroo. We have thick growth of vegetation all over.
Monu: Our national bird is donkey. We have thick growth of vegetation all over.
Vijay: Ours is a mountainous country with almost no vegetation. Our national animal is koala.



Ans .

c


  1. Explanation :

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I asked Shiva, Monu and Vijay, “What is your national dance?” and got the following replies: Shiva: Samba is our national dance. We do not like or appreciate cricket.
Monu: Salsa is our national dance. We are great lovers of aggressive cricket.
Vijay: Disco is our national dance. We are great lovers of aggressive cricket.



Ans .

a


  1. Explanation :

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Ans .

c


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In the parliament of the Ravindra Rami, all members have a peculiar habit. Of any two sentences they speak, one is false and the other is true. You record the statements of three sitting members: Rozor, Sam, and Michael.
Rozor: The President claims he is the President. I am the President.
Sam: I am the President. Rozor is the President.
Michael: I am the President. Sam knows who is the President.
Answer the following questions based on these recorded statements.



Ans .

a


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Ans .

d


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Ans .

a


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Ans .

c


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Ans .

c


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You move on. Next, you are asked to solve the mystery of who murdered Manmohan, the most influential resident of the village. You question three suspects:
Ali says, ‘‘It was me who killed Manmohan. It was Saif.”
Saif says, ‘‘It was me who killed Manmohan. It was Ramu.”
Ramu says, ‘‘It was not me who killed Manmohan. It was not Ali.”



Ans .

d


  1. Explanation :

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Type 2
In this type of questions, we have two types of people: those who always speak the truth, and those who always lie. These questions are also classified as Binary Logic questions since they are solved on the basis of two logical streams that run parallel to each other, viz: Basic Condition Logic (BCL) and Logic of the Statements (LoS).
The Basic Condition Logic flows from the fact that if a person always speaks the truth, then whatever statement he says must be true. However, in some cases, a clash might arise between the Basic Condition Logic and the Statement Logic, if it can be seen that the statement is obviously false. The best way to understand this question type is by looking at an example: You meet three inhabitants—Rohit, Mohit and Sohit—standing together. You ask Rohit “Are you a type X or type Y?” He mumbles something, which you cannot catch, so you ask Mohit, “What did Rohit say?” Mohit replies “Rohit said that he is type Y.” You look at Sohit and he says, “Do not believe Mohit, he is lying.”
Which of the following is true?
1. Rohit is a type X.
2. Mohit is a type Y.
3. Sohit is a type Y.
4. All of these.
By BCL, Sohit could be Type X or Type Y:
If Sohit is Type Y, his statement must be false. That means Mohit is not lying. Hence, Mohit should be Type X and hence his statement must be true, i.e., Rohit must have said that he is Type Y.
However, if you look at Rohit, he could not have made this statement in either case. If we assume that Rohit is Type X, he would only speak the truth and he would then say that he is Type X, not that he is Type Y.
On the other hand, if we were to assume that Rohit is a Type Y, he would only speak false. But then he could not have said that he is Type Y, since that statement would be true.

Directions for Questions 1 to 4: The following questions are based on an island called Gutar Goo on which there are only two kinds of inhabitants:
Type X: people who always speak the truth; and
Type Y: people who always lie.



Ans .

c


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Ans .

a


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Ans .

d


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Ans .

c


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Directions for Questions 5 to 10: Read the following paragraph and answer the questions that follow.
There are two types of inhabitants in Tatabalery—A type and B type. The A type of inhabitants always speak the truth and the B type of inhabitants always lie.



Ans .

d


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Ans .

c


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b


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c


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c


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c


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Directions for Questions 10 to 12:
Refer to the passage below and answer questions given below it. The inhabitants of the Island of Dreams have very bright and interesting lives. Just as we earthlings have continuity in our daily lives, the inhabitants of the Island of Dreams have continuity in both their waking lives, as well as their dreams. As a result, the inhabitants of the Island of Dreams have great difficulty in knowing whether they are awake or asleep at a given time. However, the inhabitants can be classified into two broad types—Awakers and Asleepers.
An awaker is characterised by the fact that everything they believe while they are awake is true, and everything they believe while they are asleep is false. An Asleeper on the other hand, has the characteristic that everything he believes while asleep is true, and everything he believes while awake is false.



Ans .

b


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Ans .

a


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Ans .

d


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Directions On the Island of Who Went Where, there are only two kinds of people.Type No are those who, when they ask a question, must always get a ‘No’ for an answer and Type Yes are those who must always get a ‘Yes’ for an answer to every question they ask. Based on this, answer Questions 14 to 16.



Ans .

b


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Ans .

d


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Ans .

d


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