CEMC Pascal, 2009

Number theory Difficulty 2.0 Junior Find the answer Canada

A one-dollar coin should have a mass of 7.0 g. Each individual coin may be lighter or heavier by as much as 2.14%. Joshua has a number of these coins and determines that they have a total mass of 1 kg. What is the difference between the greatest possible number and the least possible number of these coins that he could have?

(A) $4$ (B) $5$ (C) $6$ (D) $7$ (E) $8$

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