[ CSE 40 ] CIVIL SERVICE EXAMINATION REVIEWER - Logic

Civil Service Examination Reviewer

Instructions:

Please answer each question to the best of your ability. Each question is multiple choice, and only one answer per question is correct. Select the most appropriate answer from the options provided.

When you have completed all questions, click the "Submit" button at the bottom of the page to see your score. Good luck!

1. If all A are B and some B are C, which of the following conclusions is valid?

A) All A are C
B) Some A are C
C) No A are C
D) Some B are A

2. If the statement "If P then Q" is true, which of the following is false?

A) P and Q are both true
B) P is true and Q is false
C) If P is true, Q is true
D) If Q is false, P is false

3. Which of the following is a contrapositive of the statement "If it rains, then I will carry an umbrella"?

A) If I do not carry an umbrella, then it does not rain.
B) If it rains, I will carry an umbrella.
C) If I do not carry an umbrella, it rains.
D) If it does not rain, I will not carry an umbrella.

4. Which of the following is an example of a valid syllogism?

A) All dogs are animals. Some animals are cats. Therefore, some dogs are cats.
B) Some birds are parrots. All parrots are animals. Therefore, some birds are animals.
C) All humans are mortal. Socrates is a human. Therefore, Socrates is mortal.
D) No cats are dogs. All cats are animals. Therefore, no dogs are animals.

5. If the statement "No P are Q" is true, which of the following is correct?

A) Some P are Q
B) All P are Q
C) No P are Q
D) All Q are P

6. Which of the following is an example of a tautology?

A) If it rains, I will get wet. It did not rain. Therefore, I did not get wet.
B) Either it will rain tomorrow, or it will not rain tomorrow.
C) If it rains, I will carry an umbrella. It did not rain. Therefore, I did not carry an umbrella.
D) If I study hard, I will pass the exam. I studied hard. Therefore, I passed the exam.

7. Which of the following is a valid argument?

A) All men are mortal. Socrates is a man. Therefore, Socrates is mortal.
B) All students are hard-working. John is a student. Therefore, John is lazy.
C) All birds can fly. A chicken is a bird. Therefore, a chicken can fly.
D) No fish can fly. A shark is a fish. Therefore, a shark can fly.

8. Which of the following is the inverse of the statement "If it rains, I will take an umbrella"?

A) If it does not rain, I will not take an umbrella.
B) If it rains, I will not take an umbrella.
C) If I take an umbrella, it rains.
D) If it does not rain, I will take an umbrella.

9. Which of the following is an example of a disjunction?

A) If it rains, I will take an umbrella.
B) Either it will rain, or it will be sunny tomorrow.
C) If I study hard, I will pass the exam.
D) All students are intelligent.

10. What is the converse of the statement "If it is raining, then the ground is wet"?

A) If the ground is wet, then it is raining.
B) If it is raining, the ground is not wet.
C) If the ground is not wet, then it is not raining.
D) If it is not raining, then the ground is dry.

11. Which of the following statements is a contradiction?

A) All squares are rectangles, but some squares are not rectangles.
B) Some birds can fly, and some birds cannot fly.
C) If it rains, I will bring an umbrella.
D) Either I will go to the gym or I will stay home.

12. What is the negation of the statement "All doctors are intelligent?"

A) Some doctors are not intelligent.
B) No doctors are intelligent.
C) All doctors are not intelligent.
D) Some doctors are intelligent.

13. Which of the following is the correct truth table for the conjunction "p AND q"?

A) T, T, T; T, F, F; F, T, F; F, F, F
B) T, T, T; T, F, T; F, T, T; F, F, T
C) T, F, T; T, T, F; F, T, F; F, F, F
D) T, T, F; T, F, T; F, F, T; F, F, F

14. What is the logical form of the statement "If I study hard, then I will pass the test"?

A) p → q
B) q → p
C) p ∧ q
D) p ∨ q

15. Which of the following is an example of a disjunctive syllogism?

A) Either it is raining or it is snowing. It is snowing. Therefore, it is not raining.
B) Either I will go to the party, or I will stay home. I will stay home. Therefore, I will not go to the party.
C) If I study hard, I will pass the exam. I study hard. Therefore, I will pass the exam.
D) If it rains, I will bring an umbrella. It rains. Therefore, I will bring an umbrella.

16. What is the logical fallacy in the statement "Everyone who goes to the party will have fun. John went to the party, therefore John had fun?"

A) False dilemma
B) Hasty generalization
C) Post hoc ergo propter hoc
D) Affirming the consequent

17. Which of the following is a valid argument?

A) If it is raining, the ground is wet. The ground is wet, therefore it is raining.
B) If it is raining, the ground is wet. It is raining, therefore the ground is wet.
C) If it is raining, the ground is wet. The ground is not wet, therefore it is not raining.
D) If it is raining, the ground is wet. The ground is dry, therefore it is raining.

18. What is the contrapositive of the statement "If it is a dog, then it is an animal?"

A) If it is not a dog, then it is not an animal.
B) If it is not an animal, then it is not a dog.
C) If it is a dog, then it is not an animal.
D) If it is not a dog, then it is an animal.

19. Which of the following is the converse of the statement "If I am studying, then I will pass the test?"

A) If I pass the test, then I am studying.
B) If I am studying, then I will not pass the test.
C) If I pass the test, then I will be studying.
D) If I am not studying, then I will not pass the test.

20. Which of the following is an example of an affirming the consequent fallacy?

A) If it is raining, I will bring an umbrella. I brought an umbrella, therefore it is raining.
B) If I study, I will pass the exam. I passed the exam, therefore I studied.
C) Either it will rain, or it will not rain. It is raining, therefore it rained.
D) If it rains, I will carry an umbrella. I carried an umbrella, therefore it rained.

21. Which of the following is an example of an invalid argument?

A) If it is raining, the ground will be wet. The ground is wet. Therefore, it is raining.
B) If it is raining, the ground will be wet. It is raining. Therefore, the ground will be wet.
C) If I study, I will pass. I studied. Therefore, I passed.
D) If I sleep early, I will be awake in the morning. I slept early. Therefore, I am awake in the morning.

22. Which of the following is an example of a tautology?

A) If it rains, the ground will get wet; if the ground is wet, it must have rained.
B) Either it is raining or it is not raining.
C) If I go to the store, I will buy some bread. I did not go to the store, so I did not buy any bread.
D) Either I will go to school, or I will stay home. I will stay home, so I will not go to school.

23. What is the converse of the statement "If I go to the party, I will have fun?"

A) If I have fun, then I will go to the party.
B) If I do not go to the party, then I will not have fun.
C) If I do not have fun, then I will not go to the party.
D) If I have fun, then I will not go to the party.

24. Which of the following is an example of modus ponens?

A) If it rains, I will bring an umbrella. It is raining, therefore I will bring an umbrella.
B) If it rains, I will bring an umbrella. I am not bringing an umbrella, therefore it is not raining.
C) If I study, I will pass. I did not pass, therefore I did not study.
D) If I study, I will pass. I studied, therefore I passed.

25. What is the inverse of the statement "If it rains, I will bring an umbrella?"

A) If it does not rain, I will not bring an umbrella.
B) If I do not bring an umbrella, it will not rain.
C) If it rains, I will not bring an umbrella.
D) If I do not bring an umbrella, it will rain.

26. Which of the following is an example of an argument by analogy?

A) All men are mortal. Socrates is a man. Therefore, Socrates is mortal.
B) The human brain is like a computer; both process information, so the brain can be compared to a computer.
C) If it is raining, the ground is wet. The ground is wet, therefore it is raining.
D) Either I will go to work, or I will stay home. I will stay home, therefore I am not going to work.

27. Which of the following logical forms represents a valid argument?

A) If it is raining, the streets will be wet. It is raining, therefore the streets will be wet.
B) If I study, I will pass the exam. I passed the exam, therefore I studied.
C) If I go to the gym, I will get stronger. I am getting stronger, therefore I went to the gym.
D) If I read, I will understand the material. I understand the material, therefore I read.

28. Which of the following best describes a valid deduction?

A) All bachelors are unmarried. John is a bachelor, therefore John is unmarried.
B) If it rains, the streets will be wet. The streets are wet, therefore it rained.
C) If I eat pizza, I will feel full. I am feeling full, therefore I ate pizza.
D) If I take a nap, I will feel rested. I feel rested, therefore I took a nap.

29. What is the difference between a contradiction and a tautology?

A) A contradiction is always true, while a tautology is always false.
B) A contradiction is always false, while a tautology is always true.
C) A contradiction can be true or false, while a tautology can never be true.
D) A contradiction is always true, while a tautology is a specific case of a contradiction.

30. Which of the following statements is an example of the fallacy of affirming the consequent?

A) If it is raining, I will bring an umbrella. I brought an umbrella, therefore it is raining.
B) If I go to the store, I will buy groceries. I went to the store, therefore I bought groceries.
C) If it is raining, I will bring an umbrella. It is raining, therefore I brought an umbrella.
D) If I study hard, I will pass the test. I studied hard, therefore I passed the test.