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Algebra Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

There are 2016 kangaroos in a zoo. Each of them is either grey or pink, and at least one of them is grey and at least one is pink. For every kangaroo, we calculate this fraction: the number of kangaroos of the other colour divided by the number of kangaroos of the same colour as this kangaroo (including himself). Find the sum of all the 2016 fractions calculated.

(A) $2016$ (B) $1344$ (C) $1008$ (D) $672$ (E) more information required

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