Question 1077573: 1. A simple random sample of 15-year old boys from one city is obtained and their weights (in pounds) are listed below. Use a 0.01 significance level to test the claim that the population mean is greater than 147 lb.
146, 140, 160, 151, 134, 189, 157, 144, 175, 127, 164
b. Use your conclusion to determine if a boy who weights 150 lbs is considered over weight? Why?
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! Get the mean, the sd of the sample (s)
The 99%CI is mean +/- t (df=10,0.995)*s/sqrt(n)
t=3.169
mean=153.4; s=18.2
interval width is 3.169*18.2/sqrt(11)=17.39
99%CI=(136, 170.4)
This is a broad confidence interval. The popular mean can certainly be 147 lb, since it is contained in the confidence interval. There is no convincing evidence that it is greater than 147 lb. Samples of larger size that showed the same mean and sd would make it more likely, but that would have to actually occur rather than be postulated.
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