UPSC Prelims 2016 CSAT Paper II · Q35 of 79 Comprehension medium

Passage

Direction for the following 3 (three) items : Consider the given information and answer the three items that follow. Six boxes A, B, C, D, E and F have been painted with six different colours viz., violet, indigo, blue, green, yellow and orange and arranged from left to right (not necessarily either kept or painted with the colours in the same order). Each box contains a ball of any one of the following six games: cricket, hockey, tennis, golf, football and volleyball (not necessarily in the same order). The golf ball is in violet box and is not in the box D. The box A which contains tennis ball is orange in colour and is at the extreme right. The hockey ball is neither in box D nor in box E. The box C having cricket ball is painted green. The hockey ball is neither in the box painted blue nor in the box painted yellow. The box C is fifth from right and next to box B. The box B contains volleyball. The box containing the hockey ball is between the boxes containing golf ball and volleyball.

Which of the following statements is/are correct ?

  1. (a) D is painted yellow
  2. (b) F is painted indigo ✓ UPSC's answer
  3. (c) B is painted blue
  4. (d) All of the above

Why the answer is (b)

• Box A is at the extreme right (Position 6), is Orange, and contains Tennis.

• Box C is 5th from the right (Position 2), is Green, and contains Cricket.

• Box C is next to Box B, so Box B is at Position 1 or 3. Since Box A is at 6, and C is at 2, B must be at Position 1 (left of C) or Position 3 (right of C). However, the box with Hockey is between Golf and Volleyball (B). Let's determine positions first.

• The sequence of boxes is 1, 2, 3, 4, 5, 6. A is at 6. C is at 2. B is next to C, so B is at 1 or 3.

• The box with Hockey is between Golf and Volleyball (B). This implies the order is Golf-Hockey-B or B-Hockey-Golf.

• If B is at 1, Hockey cannot be between B and another box to its left. So B must be at 3. Thus, C is at 2, B is at 3.

• Since B (Volleyball) is at 3, and Hockey is between Golf and B, the order must be Golf (Pos 4) - Hockey (Pos 5) - B (Pos 3)? No, 'between' usually implies immediate adjacency in these puzzles or just positional. Let's look at the remaining boxes: 1, 4, 5. Boxes are A(6), C(2), B(3). Remaining boxes: 1, 4, 5.

• Hockey is not in D or E. Hockey is not in Blue or Yellow.

• Golf is in Violet and not in D.

• Let's place the 'Golf-Hockey-B' or 'B-Hockey-Golf' sequence. B is at 3. So Hockey is at 2 or 4? No, C is at 2. So Hockey cannot be at 2. Therefore, Hockey must be at 4 or 5? Wait, 'between' means the box with Hockey is physically located between the box with Golf and the box with Volleyball (B). Since B is at 3, the boxes are 1, 2, 3, 4, 5, 6. The only way a box is 'between' B(3) and another box is if the other box is at 1 (Hockey at 2) or 5 (Hockey at 4) or 6 (Hockey at 4 or 5). But C is at 2. So Hockey cannot be at 2. Thus, the sequence must be B(3) - Hockey(4) - Golf(5) OR Golf(1) - Hockey(2) - B(3) [Impossible as C is at 2]. So it must be B(3) - Hockey(4) - Golf(5). Or Golf(1) is not possible because Hockey would be at 2 which is C. So the order is B(3), Hockey(4), Golf(5). This means Box 4 has Hockey, Box 5 has Golf.

• So: Pos 1: ?, Pos 2: C (Green, Cricket), Pos 3: B (Volleyball), Pos 4: Hockey, Pos 5: Golf (Violet), Pos 6: A (Orange, Tennis).

• Remaining boxes for labels: D, E, F. Positions 1, 4, 5 are occupied by unknown labels? No, we have labels A, B, C, D, E, F. We placed A(6), C(2), B(3). Remaining labels D, E, F for positions 1, 4, 5.

• Golf is in Violet box and not in D. Golf is at Pos 5. So Pos 5 is not D. Pos 5 is either E or F.

• Hockey is at Pos 4. Hockey is not in D or E. So Pos 4 is not D and not E. Therefore, Pos 4 must be F.

• So F is at Pos 4. F contains Hockey.

• Remaining labels D and E for Pos 1 and Pos 5.

• Golf is at Pos 5. Golf is not in D. So Pos 5 is not D. Therefore, Pos 5 is E. Consequently, Pos 1 is D.

• So: Pos 1: D, Pos 2: C, Pos 3: B, Pos 4: F, Pos 5: E, Pos 6: A.

• Colors: C(2) is Green. A(6) is Orange. Golf(5/E) is Violet.

• Remaining colors: Indigo, Blue, Yellow for D(1), B(3), F(4).

• Hockey is in F(4). Hockey is not in Blue or Yellow. So F(4) is not Blue or Yellow. Therefore, F(4) must be Indigo.

• So F is painted Indigo. This matches option (b).

• Remaining colors for D(1) and B(3) are Blue and Yellow.

• We need to check if D is Yellow or B is Blue. The question asks which statement is correct. We established F is Indigo. Let's check the other options. Is D Yellow? We don't have enough info to distinguish D and B between Blue and Yellow yet? Wait, 'Hockey ball is neither in the box painted blue nor in the box painted yellow'. We used this to say F is Indigo. Does it constrain D or B? No. But let's re-read carefully. 'The hockey ball is neither in box D nor in box E'. We used this to say Pos 4 (Hockey) is not D or E. 'The hockey ball is neither in the box painted blue nor in the box painted yellow'. We used this to say F (Hockey) is not Blue or Yellow. So F is Indigo. This is solid. What about D and B? One is Blue, one is Yellow. Is there a constraint? 'Golf ball is in violet box'. 'Box A... orange'. 'Box C... green'. No other color constraints. So D and B can be Blue/Yellow in either order? Let's check the options. (a) D is yellow. (c) B is blue. If D is Yellow, B is Blue. If D is Blue, B is Yellow. Both are possible based on the given info? Wait, usually these puzzles have a unique solution. Let me re-check 'Hockey ball is neither in box D nor in box E'. This was used to identify F. 'Hockey ball is neither in the box painted blue nor in the box painted yellow'. This was used to identify F as Indigo. There is no constraint linking D or B to specific colors other than they are the remaining two. However, option (b) 'F is painted indigo' is definitely true. Options (a) and (c) depend on the arbitrary assignment of Blue/Yellow to D/B unless I missed a clue. Let's re-read. 'Six boxes... arranged from left to right'. 'Golf... not in D'. 'A... orange... extreme right'. 'Hockey... not in D or E'. 'C... green'. 'Hockey... not in Blue or Yellow'. 'C is 5th from right (Pos 2) and next to B'. 'B contains volleyball'. 'Hockey is between Golf and Volleyball'.

• My deduction: Pos 1(D), 2(C), 3(B), 4(F), 5(E), 6(A). Colors: 2(Green), 6(Orange), 5(Violet). Remaining: 1, 3, 4 need Indigo, Blue, Yellow. F(4) has Hockey. Hockey not in Blue/Yellow. So F(4) is Indigo. This is certain. D(1) and B(3) are Blue and Yellow. No constraint distinguishes them. Thus (a) and (c) are not necessarily true, but (b) is always true. Therefore, (b) is the correct answer.

Why the other options are wrong

(a) D is painted yellow
While D is either Blue or Yellow, there is no information to definitively assign Yellow to D over Blue, making this statement not necessarily correct.
(c) B is painted blue
While B is either Blue or Yellow, there is no information to definitively assign Blue to B over Yellow, making this statement not necessarily correct.
(d) All of the above
Since statements (a) and (c) are not definitively proven by the constraints, 'All of the above' is incorrect.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2016, held on 7 August 2016. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

Reading the answer is not the same as getting it right under a clock. Practise this question with UPSC's negative marking, and anything you miss goes into an error notebook until you get it right twice.

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