Amazon MBA: Syllogism 3 — Questions and Answers
Question 1: Statements: Some doctors are fools. Some fools are rich. Conclusion: Some doctors are rich.
- Conclusion follows
- Conclusion does not follow (Correct answer)
- Conclusion is certain
- Conclusion always true
Correct answer: Conclusion does not follow
Two particular premises with an undistributed middle prove nothing.
Question 2: Statements: All trees are green. No green thing is yellow. Which conclusion is valid?
- Some trees are yellow
- No tree is yellow (Correct answer)
- All yellow things are trees
- Some trees are not green
Correct answer: No tree is yellow
Trees are green and no green thing is yellow, so no tree is yellow.
Question 3: Statements: All boys are students. All students are players. Conclusion: All boys are players.
- Conclusion follows (Correct answer)
- Conclusion does not follow
- Data inadequate
- Conclusion is partial only
Correct answer: Conclusion follows
The two universal affirmatives chain to make all boys players.
Question 4: Statements: Some keys are locks. All locks are metals. Conclusion: Some keys are metals.
- Conclusion follows (Correct answer)
- Conclusion does not follow
- Data inadequate
- Conclusion is false
Correct answer: Conclusion follows
Keys that are locks are metals, so some keys are metals.
Question 5: Statements: No teacher is rich. Some rich people are wise. Conclusion: Some wise people are not teachers.
- Conclusion follows (Correct answer)
- Conclusion does not follow
- Conclusion is certain
- Conclusion is contradictory
Correct answer: Conclusion follows
The wise who are rich cannot be teachers, so some wise are not teachers.
Question 6: Statements: All cars are vehicles. Some vehicles are buses. Conclusion: Some cars are buses.
- Conclusion follows
- Conclusion does not follow (Correct answer)
- Conclusion is certain
- Both conclusions follow
Correct answer: Conclusion does not follow
The buses among vehicles need not be cars, so the link is not guaranteed.
Question 7: Statements: All apples are fruits. Some fruits are sweet. Some sweet things are sugary. Conclusion: Some apples are sugary.
- Conclusion follows
- Conclusion does not follow (Correct answer)
- Data adequate
- Conclusion is certain
Correct answer: Conclusion does not follow
Multiple particular links cannot tie apples to sugary with certainty.
Amazon MBA: Syllogism 3
Statements: Some doctors are fools.
Some fools are rich.
Conclusion: Some doctors are rich.