# Math quiz gone horribly wrong...HELP!!!

#### orangeb

##### New Member
I have a math quiz that I did so horrible on that the teacher gave me points for getting my name and the date right out of pity. I was so far off on every question that he said I could have gotten a higher score by leaving every page blank. If anyone can, would you please show me the correct answer and the steps to get there??? Here are the questions.

The top of the quiz stated: Remember to state explicitly on all 9 questions, the null hypothesis (Ho), alternate hypotheses (H1), rejection region (RR), level of significance (a), and the conclusion. The conclusion should include a justification, a rejection or non-rejection statement and a word description of the conclusion.

Question 1: The average hourly pay of medical typists in a large city is $15.00with a standard deviation of$2.80. The Family clinic pays its 49 medical typists an average hourly rate of $14.25. At a 5% significance level, are these employees justified in complaining that they are underpaid? Question 2: His agent claims that the average speed of a fastball thrown by the pitcher is 90mph. If the average speed of 64 randomly selected fastballs is 88 mph with a standard deviation of 3.6 mph, should we reject the agent's claim? ( use a 1% level of significance) Question 3: Company officials say that the average retail price of their Zoids computer game is$24.50. Sixteen games are purchased at randomly selected stores; the average price is $25.25 with a standard deviation of$2.25. Are we justified in our suspicion that the average price is actually more that the company admits? (Use a = 0.01.)

Question 4: The U.S. Census Bureau recently indicated that 23% of all American adults have more than one job. A random survey of 68 adults finds that 21 of them hold multiple jobs. At the 5% level of significance, can we accept the government's claim?

Question 5: The math department claims that the average SAT score of it's top students is 20 points higher than the average score of the top Business majors. A study obtained the following data:
Number of Students 34 36
Average SAT score 951 920
Standard deviation 65 51

Test the Math Department's claim at the 1% level of significance.

Question 6: For the alumni of the graduating classes from the years 1988 to 1991, the following data is available:
1988 1989 1990 1991

Made a contribution? YES 469 582 731 646
NO 218 371 589 488

Using a 5% level of significance, test the null hypothesis that the percentage of graduates who contributed money is the same across all these graduating classes.

Question 7: A local advertising firm wanted to know if any one of the local stations has a significantly larger proportion of the television viewers of the evening news broadcasts. The firm randomly selected 1,000 people and asked them to specify which station's news program they prefer. The responses were as follows:

TV Station A B C D
Number of viewers 241 288 263 208

Using a 1% level of significance, test the null hypothesis that these 4 TV stations have equal shares of the evening news audience.

Question 8: A study was conducted to investigate the relationship between the weight and diastolic blood pressure of American males between 40 and 50 years of age. The following results were obtained:

Weight, x: 182 169 171 193 185 152 141 199 220Blood Pressure, y: 90 81 84 92 88 79 78 90 97

A: Compute the coefficient of correlation for this data.
B: At the 5% level, is the coefficient of correlation significant? Explain.

Question 9: A sociologist believes that there is a tendency for tall men to marry tall women. To determine the nature of such a relationship, the heights of the men and women from 10 randomly selected couples are recorded:

Wife, x: 62 67 61 64 63 63 65 66 68 71
Hubby, y: 66 67 65 66 67 69 67 68 72 74

A. Determine the least-squares prediction equation.
B. Draw a scatter diagram for this data
C. Find at least two points and draw the regression line on the scatter diagram.