Jamestown Steel Company manufactures and assembles desks and other office equipment at several plants in western New York State. The weekly production of the Model A325 desk at the Fredonia Plant follows the normal probability distribution with a mean of 200 and a standard deviation of 16. Recently, because of market expansion, new production methods have been introduced and new employees hired. The vice president of manufacturing would like to investigate whether there has been a change in the weekly production of the Model A325 desk. Suppose he wants the significance level to be 0.01.

denote %u03BC to be the population mean of weekly production of the Model A325 after new methods, set up the null hypothesis the vice president wants to test:

a. %u03BC = 200
b. %u03BC %u2260 200
c. %u03BC > 200
d. %u03BC < 200
e. %u03BC %u2264 200
f. %u03BC %u2265 200

2.(continues from the Jamestown question) After taking a sample of 50 obs, you find the sample mean to be 203.5, therefore your test statistic will take value of:

a. 203.5 - 200
b. (203.5 - 200) / 16
c. 203.5 /16
d. (203.5 - 200) / (16/sqrt(50))
where sqrt(50) takes square root of 50, the sample size

3. (continues from the Jamestown question) the rejection region is :

a. z %u2265 z0.01
b. z %u2264 - z0.01
c. z %u2265 z0.01 or z %u2264 - z0.01
d. z %u2265 z0.005
e. z %u2264 - z0.005
f. z %u2265 z0.005 or z %u2264 - z0.005

4. Suppose in the previous problem the vice president wants to know whether there has been an increase in the number of units assembled. Now how should you set up the null hypothesis?

a. %u03BC = 200
b. %u03BC %u2260 200
c. %u03BC > 200
d. %u03BC < 200
e. %u03BC %u2264 200
f. %u03BC %u2265 2000