Watson-Glaser Critical Thinking Appraisal Drawing Deductive Conclusions Questions and Answers 4

Question 1

Premises: All physicians are college graduates. Some college graduates are wealthy. Conclusion: Some physicians are wealthy.

Accepted Answer

The conclusion does not follow

Answer

The 'some wealthy college graduates' may not overlap with physicians at all, so wealth among physicians cannot be deduced.

Question 2

Premises: Either the project is on schedule or it is over budget. The project is not over budget. Conclusion: The project is on schedule.

Accepted Answer

The conclusion follows

Answer

This is a valid disjunctive syllogism: given A or B, and not B, A must be true.

Question 3

Premises: All animals that are mammals breathe air. Whales breathe air. Conclusion: Whales are mammals.

Accepted Answer

The conclusion does not follow

Answer

Breathing air is a property of all mammals but may also apply to non-mammals, so the conclusion commits the fallacy of affirming the consequent.

Question 4

Premises: No fast-food restaurant in the city serves lobster. The Harbor Grill is in the city and serves lobster. Conclusion: The Harbor Grill is not a fast-food restaurant.

Accepted Answer

The conclusion follows

Answer

By contraposition: if it served lobster and no fast-food restaurant in the city does, then it cannot be a fast-food restaurant.

Question 5

Premises: All red cards in the deck are hearts or diamonds. This card is a spade. Conclusion: This card is not red.

Accepted Answer

The conclusion follows

Answer

Since all red cards are hearts or diamonds, a spade cannot be red — the conclusion follows validly by modus tollens.

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 4