A health professional obtains records for 31 patients who have undergone a certain surgical procedure and finds the average length of stay is 5.74 days with a standard deviation of 1.23 days. Using =0.01=0.01, is there evidence to suggest the actual average length of stay for this surgical procedure is 5 days? What are the hypotheses?

• H0:x=5.74H0:x=5.74 vs H1:x5.74H1:x5.74
• H0:=5.74H0:=5.74 vs H1:5.74H1:5.74
• H0:x=5H0:x=5 vs H1:x5H1:x5
• H0:=5H0:=5 vs H1:5H1:5

Calculate the test statistic using the correct letter.

• z=3.35z=3.35
• t=3.35t=3.35
• t=3.35t=-3.35
• z=3.35z=-3.35

Determine the critical values.

• 2.5762.576
• 2.4492.449
• 2.4572.457
• 2.3262.326
• 2.7442.744
• 2.7392.739
• 2.752.75

State your decision.

• Fail to reject H0H0
• Accept H0H0
• Reject H0H0

The correct conclusion is that we Select an answer can can maybe cannot conclude that the average length of stay of Select an answer all sampled randomly selected surgeries of this type Select an answer is more than is different from is is less than Select an answer 3.35 5 5.74 days. What level of concern do you have for the validity of your results?

• Extreme - we should not use any part of what we've done to make a conclusion
• None - our sample size is larger than 30 so there should be no problem with the conclusion
• Low - our sample size is near 30, so while that's likely sufficient for XX to be approximately normally distributed, seeing that the original data isn't extremely skewed would make us feel more comfortable
• Moderate - the original data is not normally distributed which is an assumptions violation