Suppose position number 30 relegated to position number 70. The 70th will be upgraded to number 69, 69th to 68 and so downwards until the merit number 30. 30th being accommodated at number 70, the merit number of 71 will remain unchanged. that is how one demotion can affect 40 positions in total. Same might happen somewhere in 200s or 300s... Thereby affecting 266 people in its totality. That was not too hard to understand by the way.

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