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Question

This question is from the book statistics 9th ed robert s. witte and john s. witte on page 81. Standard deviation

 

4.8B) When not interrupted artificially, the duration of human pregnancies can be described, we'll assume, by a mean of 9 months (270 days) and a standard deviation of one-half month (15 days).

A small minority of all babies will arrive sooner than _____?

Answer 1

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