Data on lowbirth weight habits were collected over a 2year p

Data on low-birth weight habits were collected over a 2-year period by 14 patting centers of the National Institute of Child Halts and Hares Development Neonatal

Solution

a)

Yes, because there are 1084 of them, so they are many enough to treat them as a population.

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b)

As

z = (x-u)/sigma

Then

z = (86-66)/12 = 1.666666667 [ANSWER]

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c)

As

z = (x-u)/sigma

Then

z = (86-108)/12 = -1.833333333 [ANSWER]

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D)

If the baby was born at the center with mean 66 days, then that baby can be considered staying longer than usual.

If the baby was born at the center with mean 108 days, then that baby can be considered staying shorter than usual.