An industrial supplier has shipped a truckload of teflon lub

An industrial supplier has shipped a truckload of teflon lubricant cartridges to an aerospace customer. The customer has been assured that the mean weight of these cartridges is in excess of the 15 ounces printed on each cartridge. To check this claim, a sample of n=23 cartridges are randomly selected from the shipment and carefully weighed. Summary statistics for the sample are: x-bar=15.11 ounces, s=.23 ounce. To determine whether the supplier\'s claim is true, consider the test, Ho:=15 vs. Ha: >15, where is the true mean weight of the cartridges. Calculate the value of the test statistic.

Solution

Getting the test statistic, as              
              
X = sample mean =    15.11          
uo = hypothesized mean =    15          
n = sample size =    23          
s = standard deviation =    0.23          
              
Thus, t = (X - uo) * sqrt(n) / s =    2.293658555 [ANSWER, TEST STATISTIC]