Watson-Glaser Critical Thinking Appraisal Drawing Deductive Conclusions Questions and Answers 3

Question 1

Premises: All managers attend the weekly briefing. Sandra is a manager. Conclusion: Sandra attends the weekly briefing.

Accepted Answer

The conclusion follows

Answer

Since all managers attend and Sandra is a manager, the conclusion follows necessarily by universal instantiation.

Question 2

Premises: No reptiles are warm-blooded. All snakes are reptiles. Conclusion: Some snakes are warm-blooded.

Accepted Answer

The conclusion does not follow

Answer

If no reptiles are warm-blooded and all snakes are reptiles, then no snakes can be warm-blooded — so the conclusion contradicts the premises.

Question 3

Premises: If it rains, the game is cancelled. The game was not cancelled. Conclusion: It did not rain.

Accepted Answer

The conclusion follows

Answer

This is the valid logical form modus tollens: if P→Q and ¬Q, then ¬P; therefore the conclusion follows.

Question 4

Premises: Some students passed the exam. All students who passed received a certificate. Conclusion: All students received a certificate.

Accepted Answer

The conclusion does not follow

Answer

The premises only guarantee that the students who passed received certificates, not all students, so the conclusion is too strong.

Question 5

Premises: Every employee who works overtime earns a bonus. James earned a bonus. Conclusion: James worked overtime.

Accepted Answer

The conclusion does not follow

Answer

Earning a bonus may have other causes; the premises do not state that overtime is the only way to earn a bonus, so affirming the consequent is a fallacy.

Watson-Glaser Critical Thinking Appraisal Practice Test

Watson-Glaser Critical Thinking Appraisal Practice Test

Watson-Glaser Critical Thinking Appraisal Drawing Deductive Conclusions Questions and Answers 3