Ex. 6,8

the hypothesis that the selection constituted a random sample? 6. It is known that the value received at a local receiving station is equal to elec the value sent plus a random error that is normal with mean 0 and stan- que dard deviation 2. If the same value is sent 7 times, compute the p value can for the test of the null hypothesis that the value sent is equal to 14, if the test values received are car no 14.6, 14.8, 15.1, 13.2, 12.4, 16.8, 16.3 13. Th 7. Historical data indicate that household water use tends to be normally sta distributed with a mean of 360 gallons and a standard deviation of 40 m gallons per day. To see if this is still the situation, a random sample of 200 WO households was chosen. The average daily water use in these households 15 was then seen to equal 374 gallons per day. (a) Are these data consistent with the historical distribution? Use the 14. Su 5 percent level of significance. ta (b) What is the p value? a 8. When a certain production process is operating properly, it produces ta items that each have a measurable characteristic with mean 122 and stan- of dard deviation 9. However, occasionally the process goes out of control, le and this results in a change in the mean of the items produced. Test the 15. In hypothesis that the process is presently in control if a random sample of 1 10 recently produced items had the following values: a 123, 120, 115, 125, 131, 127, 130, 118, 125, 128 Specify the null and alternative hypotheses, and find the p value. 9.3.1 9. A leasing firm operates on the assumption that the annual number of So far which