In a certain code, '256' means 'red colour chalk', '589' means 'green colour flower' and '254' means 'white colour chalk'. The digit in the code that indicates 'white' is
- (a) 2
- (b) 4 ✓ UPSC's answer
- (c) 5
- (d) 8
Why the answer is (b)
["- Compare the first code '256' (red colour chalk) and the third code '254' (white colour chalk).", "- Both codes share the digits '2' and '5', which correspond to the common words 'colour' and 'chalk'.", "- The unique digit in the first code is '6', which must represent 'red'.", "- The unique digit in the third code is '4', which must represent 'white'.", "- Therefore, the digit indicating 'white' is 4, making option (b) the correct answer."]
Why the other options are wrong
- (a) 2
- Digit 2 is common to 'red colour chalk' and 'white colour chalk', so it represents either 'colour' or 'chalk', not 'white'.
- (c) 5
- Digit 5 is common to 'red colour chalk' and 'white colour chalk', so it represents either 'colour' or 'chalk', not 'white'.
- (d) 8
- Digit 8 appears in 'green colour flower' and is not present in the code for 'white colour chalk'.
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.