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1

Part of 2007 Paraguay Mathematical Olympiad

Problems(1)

Paraguayan National Olympiad 2007, Level 3, Problem 1

Source:

8/31/2014
A list with 20072007 positive integers is written on a board, such that the arithmetic mean of all the numbers is 1212. Then, seven consecutive numbers are erased from the board. The arithmetic mean of the remaining numbers is 11.91511.915. The seven erased numbers have this property: the sixth number is half of the seventh, the fifth number is half of the sixth, and so on. Determine the 77 erased numbers.