Xtron Electrics manufactures dental X-ray tubes. Health Canada has warned that they are not fulfilling regulations for Radiation Emitting Devices. For a sample of 20 X-ray tubes in operation, their mean peak-value voltage ( = 52 kV) is acceptable, but it is claimed that the standard deviation is greater than the 2.6 kV allowed (based on Federal Regulation C.R.C., C.1370). The standard deviation for the sample was 2.8 kV. At the 0.05 level of significance, test the claim that Xtron's product is failing to meet the requirement of a maximum standard deviation of 2.6 kV.
Use the traditional method to test the given hypotheses. Follow the steps outlined and draw the appropriate graph. In all cases, assume that the population is normally distributed and that the sample has been randomly selected.