Posted by Michael on Saturday, November 9, 2013 at 9:08am.
According to a study by the Centers for Disease Control, the national mean hospital stay after childbirth is 2.1 days. Reviewing records at her own hospital, a hospital administrator calculates that the mean hospital stay for a random sample of 81 women after childbirth is 2.3 days with a standard deviation of 1.2 days.
Test the claim that the mean hospital stay after childbirth for this hospital is significantly longer than the national mean of 2.1 days.
What is the pvalue?
A) 0.9312
B) 0.0688
C) 0.1376
D) 0.164

Statistics  PsyDAG, Saturday, November 9, 2013 at 10:59am
Z = (mean1  mean2)/standard error (SE) of difference between means
SEdiff = √(SEmean1^2 + SEmean2^2)
SEm = SD/√n
If only one SD is provided, you can use just that to determine SEdiff.
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.
Answer This Question
Related Questions
 Statistics  According to a study by the Centers for Disease Control, the ...
 Statistics  According to a study by the Centers for Disease Control, the ...
 Statistics  According to a study by the Centers for Disease Control, the ...
 Statistics  According to a study by the Centers for Disease Control, the ...
 Statistics  Upon examining its records, a hospital computes the distribution of...
 STATISTICS  Length of Hospital Stays: The average length of “short” hospital ...
 English  1. She works as a cleaner in/at a hospital. (Which preposition do I ...
 statistics  A study involving the economic burden of congestive heart failure ...
 English  Posted by rfvv on Sunday, October 10, 2010 at 9:17pm. 1. What does a ...
 math, pre statistics  Hospital records indicated that maternity patients ...
More Related Questions