The postal service groups first-class mail as letters, cards, flats, or parcels. Over a
Chapter 0, Problem 37(choose chapter or problem)
The postal service groups first-class mail as letters, cards, flats, or parcels. Over a period of three weeks, one item of each kind was sent from a particular postal administrative center. The total time in transit was recorded. A statistical software package was then used to perform the analysis. The results follow.
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