UPSC Prelims 2013 · CSAT
Question 18: Logical Reasoning and Mental Ability
The music director of a film wants to select four persons to work on different aspects of the composition of a piece of music. Seven persons are available for this work; they are Rohit, Tanya, Shobha, Kaushal, Kunal, Mukesh and Jaswant. Rohit and Tanya will not work together. Kunal and Shobha will not work together. Mukesh and Kunal want to work together. Which of the following is the most acceptable group of people that can be selected by the music director ?
AnswerUPSC’s answer is (c).
Test each group against the conditions: Rohit and Tanya are never together, Kunal and Shobha are never together, and Mukesh and Kunal come as a pair. (a) has Kunal with Shobha, so it fails. (b) and (d) both put Rohit with Tanya, so they fail; (d) also has Mukesh without Kunal. (c) Tanya, Mukesh, Kunal and Jaswant keeps Mukesh with Kunal and contains neither Rohit nor Shobha, so nothing is broken.
Why each option is right or wrong
- (a) Wrong. Kunal and Shobha will not work together.
- (b) Wrong. Rohit and Tanya will not work together.
- (c) Right. Mukesh and Kunal are together, with no clash among the others.
- (d) Wrong. It has Rohit with Tanya and Mukesh without Kunal.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2013, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.