Explain the answer. Answers are in the Instructor’s Edition of this text.Postage reform.  ...

Explain the answer. Answers are in the Instructor’s Edition of this text.

Postage reform.   A new postage system is being discussed. Postage for a letter would depend on its weight and would be a whole number of cents. Proponents claim that any appropriate postage amount could be achieved using only 5 cent and 11 cent stamps. The Postal Service would have to print only two types of stamps and these stamps would work even as rates go up. What is the largest whole number amount of postage that could not be formed using only these two types of stamps? Explain why every amount thereafter could be formed using only these two types of stamps.

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