UPSC Prelims 2017 · CSAT
Question 70: Logical Reasoning and Mental Ability
A, B, C, D, E, F and G are Lecturers from different cities—Hyderabad, Delhi, Shillong, Kanpur, Chennai, Mumbai and Srinagar (not necessarily in the same order) who participated in a conference. Each one of them is specialized in a different subject, viz., Economics, Commerce, History, Sociology, Geography, Mathematics and Statistics (not necessarily in the same order). Further
- 1.Lecturer from Kanpur is specialized in Geography
- 2.Lecturer D is from Shillong
- 3.Lecturer C from Delhi is specialized in Sociology
- 4.Lecturer B is specialized in neither History nor Mathematics
- 5.Lecturer A who is specialized in Economics does not belong to Hyderabad
- 6.Lecturer F who is specialized in Commerce belongs to Srinagar
- 7.Lecturer G who is specialized in Statistics belongs to Chennai
To which city does the Lecturer specialized in Economics belong?
AnswerUPSC’s answer is (b).
Economics belongs to A. Using the clues, D is Shillong, C is Delhi, F is Srinagar and G is Chennai, so A, B and E hold Hyderabad, Kanpur and Mumbai. A is not from Hyderabad, and Kanpur's lecturer specialises in Geography, not Economics, so A is from Mumbai. Eliminate the fixed cities first, then use the exclusions for what remains.
Why each option is right or wrong
- (a) A is not from Hyderabad, by the fifth clue.
- (b) Correct: A cannot be Hyderabad or Kanpur, so A is from Mumbai.
- (c) Mumbai is one of the two named cities, so neither is wrong.
- (d) The clues settle the city.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2017, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.