Question 1

Either the orangutan is not angry, or he frowns upon the world. A. The orangutan frowns upon the world. B. The orangutan is not angry. C. The orangutan does not frown upon the world. D. The orangutan is angry.

Accepted Answer

It is an example of either a or b type: Consider CB it implies - b- a that is logically correct. DA - it implies - a → b that is also logically correct. AB it implies - a → - b that is logically incorrect. Hence both CB and DA are correct.

Question 2

Either Ravana is a demon, or he is a hero. A. Ravana is a hero. B. Ravana is a demon. C. Ravana is not a demon. D. Ravana is not a hero.

Accepted Answer

It is an example of either a or b type: CD a → - b that is logically incorrect. BA a → b that is also logically incorrect. DB b → a that is also logically correct CA - a → b that is also logically correct

Question 3

Whenever Rajeev uses the internet, he dreams about spiders. A. Rajeev did not dream about spiders. B. Rajeev used the internet. C. Rajeev dreamt about spiders. D. Rajeev did not use the internet.

Accepted Answer

Same as above AD is logically correct

Question 4

If I talk to my professors, then I do not need to take a pill for headache. A. I talked to my professors. B. I did not need to take a pill for headache. C. I needed to take a pill for headache. D. I did not talk to my professors.

Accepted Answer

Same as above Ab and CD are logically correct.

Question 5

A. Only if the water level in the coastal areas rises, then the people change their lifestyle. B. People change their lifestyle only if they are rewarded. C. If people are rewarded, then they will not change their lifestyle. D. If the temperature ri…

Accepted Answer

(H) Water level in the coast area does not rise From (D) → Temperature will not rise From (F) → People change their lifestyle From (B) → People will be rewarded, which is given in G.

Question 6

A. If Kumar sings, then the audiences sleep. B. If Kumar sings, then the audiences dance. C. Unless audience do not dance, the concert will be successful. D. Only if the audience dance, the concert will be successful. D. Only if the audience dance, …

Accepted Answer

(G) → Vina dances From (E) → Kumar sings From (B) → Audience dance From (C) → Concert will be successful, which is given in H.

Question 7

Manisha will eat the orange if Rajesh does not cook. Bases on the information above which of the following must be true

Accepted Answer

The conclusion should be if Manisha ate the orange, then Rajesh did not cook.

Question 8

Look at the sentences given below (i) If the contract is valid, then X is liable. (ii) If X is liable, he will be bankrupt. (iii) If the bank loans him money, he will not go bankrupt. Select the statement that is consistent with the above statements

Accepted Answer

From first two statements we can conclude: 'if the contract is valid then X would be bankrupt.' Statement 3 is 'If he goes bankrupt, then the bank will not loan him the money.' From above two statements, we have: If the contract is valid, then the bank will not loan him the money. This is reflected in option B.

Question 9

Unless teacher is agree, the class will continue and three will be a test.

Accepted Answer

This belongs to Type 3: "Unless X, Y and Z" this statement implies that: (~ X → Y or Z) (~ Y or/and ~ Z → X) Given in option (B)

Question 10

If it is a holiday then Suvrojyoti will play cricket or will watch movie.

Accepted Answer

This is the situation of "If X then Y or Z" it implies that: (i) (X → Y or Z) (ii) (~ Y and ~ Z → ~ X) (iii) (X and ~ Z → Y) (iv) (X and ~ Y → Z) given in option (B)

Question 11

If you study then you will pass the exam and will get a good girlfriend .

Accepted Answer

This is of type 1:- "If X then Y and Z" This statement implies that: (i) (X → Y and Z) (ii) (~ Y or/and ~ Z → ~ X) given in option B

Question 12

Unless students are agree, the class will continue and Institute will remain open.

Accepted Answer

This belongs to Type 3:- "Unless X, Y and Z" This statement implies that: (i) (~ X → Y or Z) (ii) (~ Y or/and ~ Z → X) Given in option (B)

Question 13

If Ricky singh is not at Pioneer Career then he is at his sleeping or watching movie.

Accepted Answer

This is the situation of "If X then Y or Z" it implies that: (i) (X → Y or Z) (ii) (~ Y and ~ Z → ~ X) (iii) (X and ~ Z → Y) (iv) (X and ~ Y → Z) given in option (A)

Question 14

If it is not raining then I will not walk slow but I will walk at least 4 km.

Accepted Answer

This is the situation of "If X then Y and Z" it implies that: (i) (X → Y and Z) (ii) (~ Y or/and ~ Z → ~ X ) given in option (C)

Question 15

Only if it is a national holiday, Pioneer career is not open and employee enjoy together.

Accepted Answer

This is the situation of "Only if X then Y and Z" it implies that: (i) (Y and Z → X) (ii) (~ X → ~ Y or/and ~ Z) given in option (C)

Question 16

If a student sees a teacher in the class he would not sleep in the class, One day, a student does not see a teacher in the class. Which of the following statements is true?

Accepted Answer

Here let X be the event that the student sees a teacher. And event Y be the event that he is sleeping. We have been given that X → ~ Y. However, we do not know anything about ~ X, and the question asks us what Y will be if ~ X. ∴ We cannot conclude anything.

Question 17

In all family photos, if Geeta is present, her two sisters are also present. A certain photo features five members of his family. Among the people in that photo are Geeta's parents with their son. Which of these statements is necessarily true?

Accepted Answer

Let X be the event that Geeta is present in the photo and event Y that her sister are present. Given that X → Y. As per the given information in the photo already has three people (Geeta's parents with their son 3 persons so remaining can be only 2 persons). Thus, Geeta cannot be in the photo.

Question 18

(i) Doing well in CAT implies doing well in JMET. (ii) Good JMET results ensure that you get into one of the IITs or IISc. (iii) Poor CAT results do not get you an admission into any of the IIMs.

Accepted Answer

Admission in one of the IIM's ensures good performance in CAT. This implies doing well in JMET. This ensures that you get into one of the IITS or IISC So option D is true.

Question 19

(i) Whenever there is a fire, the fire alarm goes off (ii) If the sprinklers do not start, the fire alarm does not go off. (iii) If the sprinklers start, an automatic alarm is set off at the fire department.

Accepted Answer

Lets eliminate options one by one- Option A: Cannot be true since we cannot infer anything if we know that an automatic alarm is set off at the fire department. Option B: If sprinklers do not start then the fire alarm doesn't go off. Further we cannot say anything about the automatic alarm at the fire department. Option C: When there is a fire the fire alarm goes off so sprinklers start. Hence an automatic alarm is set off at the fire department. Option (D) is similarly ruled out.

Question 20

(i) Whenever milk is kept in front of a child, he/she starts crying. (ii) Children cry if they are hungry. (iii) Unhappy children are hungry.

Accepted Answer

Lets eliminate options one by one- Option A: Child is hungry, So, from (ii) child is crying, but we cannot say anything about the child liking milk or not. Option B: A child is crying, but from this we cannot say anything regarding the child being hungry or unhappy. Option C: The statements are not speaking about the happy child. Option D: Unhappy children are hungry and hungry children cry. So choice (D) is most logically supported.

Logical Connectives Questions