Passage

Directions for the following 3 (three) items : Consider the given information and answer the three items that follow. 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?

(a) Hyderabad
(b) Mumbai ✓ UPSC's answer
(c) Neither Hyderabad nor Mumbai
(d) Cannot be determined as data are inadequate

Why the answer is (b)

• The cities left for A, B and E are Hyderabad, Kanpur and Mumbai (C Delhi, D Shillong, F Srinagar, G Chennai).

• A teaches Economics, so A is not the Kanpur (Geography) lecturer; clue 5 says A is not from Hyderabad.

• So the Economics lecturer, A, is from Mumbai, option (b).

Why the other options are wrong

(a) Hyderabad: Lecturer A (Economics) is explicitly stated not to belong to Hyderabad in clue 5.
(c) Neither Hyderabad nor Mumbai: The data is sufficient to determine that A belongs to Mumbai, so it is not 'neither'.
(d) Cannot be determined as data are inadequate: The constraints allow for a unique solution where A is from Mumbai, so the data is adequate.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2017, held on 18 June 2017. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.