Eugene Chan's answer to Pikachu's Other Countries All question.

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Eugene Chan
Eugene Chan's answer
57 answers (Tutor Details)
1st
The question is poorly phrased. For 864 to be the answer, the arrangement is 2 alphabets followed by 4 digits. i.e. the digits cannot be at the 1st and 2nd positions.

If you want 864 as the answer, follow method (2)
If you want the proper way of solving this qn, refer to method (1).
I put both methods for you.