QUESTION 6

Mike runs for the president of the student government and is interested to know whether the proportion of the student body in favor of him is significantly more than 50 percent. A random sample of 100 students was taken. Fifty-five of them favored Mike. At a 0.05 level of significance, it can be concluded that the proportion of the students in favor of Mike:

	a.	is significantly greater than 50 percent because 55 percent of the sample favored him.
	b.	is not significantly greater than 50 percent.
	c.	is significantly greater than 55 percent.
	d.	is not significantly different from 55 percent.

QUESTION 7

The R.D. Wilson Company makes a soft drink dispensing machine that allows customers to get soft drinks from the machine in a cup with ice. When the machine is running properly, the average number of fluid ounces in the cup should be 14. Periodically the machines need to be tested to make sure that they have not gone out of adjustment. To do this, six cups are filled by the machine and a technician carefully measures the volume in each cup. In one such test, the following data were observed:

14.25	13.7	14.02
14.13	13.99	14.04

Based on these sample data, which of the following is true if the significance level is .05?

	a.	No conclusion can be reached about the status of the machine based on a sample size of only six cups.
	b.	The null hypothesis cannot be rejected since the test statistic is approximately t = 0.20, which is not in the rejection region.
	c.	The null hypothesis can be rejected since the sample mean is greater than 14.
	d.	The null can be rejected because the majority of the sample values exceed 14.

QUESTION 8

A recent study of 15 shoppers showed that the correlation between the time spent in the store and the dollars spent was 0.235. Using a significance level equal to 0.05, which of the following is true?

	a.	The null hypothesis that the population mean is equal to zero should be rejected and we should conclude that the true correlation is not equal to zero.
	b.	Based on the sample data there is not enough evidence to conclude that the true correlation is different from zero.
	c.	The sample correlation coefficient could be zero since the test statistic does not fall in the rejection region.
	d.	The null hypothesis should be rejected because the test statistic exceeds the critical value.

QUESTION 9

A recent study by a major financial investment company was interested in determining whether the annual percentage change in stock price for companies is linearly related to the annual percent change in profits for the company. The following data was determined for 7 randomly selected companies:

% Change Stock Price	% Change in Profit
8.4	4.2
9.5	5.6
13.6	11.2
-3.2	4.5
7	12.2
18.4	12
-2.1	-13.4

Based upon this sample information, what portion of variation in stock price percentage change is explained by the percent change in yearly profit?

	a.	Approximately 70 percent.
	b.	Nearly 19 percent.
	c.	About 49 percent.
	d.	None of the above.

QUESTION 10

In a multiple regression analysis involving 15 independent variables and 200 observations, SST = 800 and SSE = 240. The adjusted coefficient of determination is:

	a.	0.15.
	b.	0.50.
	c.	0.66.
	d.	0.70.