The mean weight of newborn infants at a community hospital is 6.6 pounds.A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0,7.3,6.0,8.8,6.8,8.4,and 6.6 pounds.What is the decision for a statistical significant change in average weights at birth at the 5% level of significance?
A)Fail to reject the null hypothesis and conclude the mean is 6.6 lb.
B)Reject the null hypothesis and conclude the mean is higher than 6.6 lb.
C)Reject the null hypothesis and conclude the mean is lower than 6.6 lb.
D)Cannot calculate because population standard deviation is unknown.

Question

Quizplus · Accepted Answer

The sample mean is not significantly different from the population mean of 6.6 pounds at the 5% significance level, so we fail to reject the null hypothesis.

The Mean Weight of Newborn Infants at a Community Hospital