A Statement followed by Conclusion-I and Conclusion-II is given below. You have to take the Statement to be true even if it seems to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statement, disregarding the commonly known facts. Statement : Some radios are mobiles. All mobiles are computers. Some computers are watches. Conclusion-I : Certainly some radios are watches. Conclusion-II : Certainly some mobiles are watches. Which one of the following is correct ?
- (a) Only Conclusion-I
- (b) Only Conclusion-II
- (c) Both Conclusion-I and Conclusion-II
- (d) Neither Conclusion-I nor Conclusion-II ✓ UPSC's answer
Why the answer is (d)
• The statement 'Some radios are mobiles' establishes a partial overlap between radios and mobiles, but does not imply all radios are mobiles.
• The statement 'All mobiles are computers' means the set of mobiles is entirely contained within the set of computers.
• The statement 'Some computers are watches' indicates a partial overlap between computers and watches, but does not specify if these computers are the same as the mobiles.
• Since the overlap between computers and watches is not guaranteed to include the subset of mobiles, Conclusion-II ('Some mobiles are watches') does not logically follow.
• Similarly, there is no direct or transitive link established between radios and watches through the given premises, so Conclusion-I ('Some radios are watches') does not follow.
• Therefore, neither conclusion can be definitively derived from the statement, making option (d) the correct answer.
Why the other options are wrong
- (a) Only Conclusion-I
- Conclusion-I does not follow because there is no logical connection established between radios and watches in the premises.
- (b) Only Conclusion-II
- Conclusion-II does not follow because the 'some computers' that are watches are not necessarily the same as the 'all mobiles' that are computers.
- (c) Both Conclusion-I and Conclusion-II
- Both conclusions fail to follow logically from the given premises as explained in the individual analyses.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2021, held on 10 October 2021. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.