No student is lazy — Syllogisms Aptitude Question
No student is lazy: Statements: No student is lazy. Some lazy people are rich. Conclusions: I. Answer and worked solution on CodeKairo.
- Topic: Syllogisms
- Section: Logical Reasoning
- Difficulty: Hard
- Time target: 90 seconds
Question
Statements:
- No student is lazy.
- Some lazy people are rich.
Conclusions: I. Some rich people are not students. II. No rich person is a student.
Which conclusion follows?
Options
- Only I
- Only II
- Both
- Neither
Show the answer and the worked solution
Correct answer: A. Only I
Worked solution
- Some lazy people are rich; no lazy person is a student; so those rich people are not students. Conclusion I follows.
- Other rich people (not lazy) could be students, so conclusion II is too strong.
Answer: Only I.
The idea
'Some' conclusions are safer than 'no' or 'all'. Ask whether a single counter-drawing can break the conclusion; if yes, it does not follow.
Shortcut. 'Some lazy are rich' plus 'no lazy is a student' gives the standard 'some rich are not students'; a 'no' conclusion needs both premises universal.
Common trap. "Both" — stretching 'some rich people are not students' to 'no rich person is a student'; rich people who are not lazy may still be students.