a. Negatively skewed b. Symmetrical c. Positively skewed d. None of the above 3. The slope of a linear regression line gives a measure of the: a. Change in the value of the independent variable for a unit change in the value of the dependent variable. b. Change in the value of the dependent variable for a unit change in the value of the independent variable. c. Predicted value of the dependent variable for a particular value of the independent variable. d. b and c, but not a.

4. If repeated samples of size 25 are drawn from a large population that has a standard deviation of 4, the standard error of the mean is: a. 4 b. 5 c. 0.8 d. 25 5. A confidence interval has a lower confidence limit of 33 and upper confidence limit of 45. The maximum error of estimate is equal to: a. 33 b. 12

c. 45 d. 6 6. Which of the following is the first step in calculating the median of a data set? a. Arrange the data in increasing order.

b. Average the middle two values of the data set. c. Determine the relative weights of the data values in terms of importance.

d. None of a,b and c. 7. The difference between the first and third quartile is called: a. Midrange b. Midquartile

c. Variance d. Interquartile range. 8. Suppose the least squares regression line is y= 5 -2x has been determined for a set of data. Which of the following is true for this situation? a. The y intercept for the line is 5. b. The slope of the line is negative.

c. The value of y for x = 1 is equal to 3. d. All of the above. 9. Suppose that a normally distributed population of size 144 has a mean of 24. What is the mean of the sampling distribution of sample means for samples of size 25 drawn from this population? a. 24

b. 2 c. 4.8 d. Cannot be determined from the information given. 10. The average height of 25 students in a year 10 mathematics class is known to be 66 inches, with a standard deviation of 6 inches. In constructing a 95% confidence interval for the average height of all year 10 students, we would use: a. The normal distribution with 24 degrees of freedom.

b. The t distribution with 24 degrees of freedom. c. The t distribution with 65 degrees of freedom. d. The t distribution with 25 degrees of freedom. 11. Which of the following is not affected by extreme values? a. Median b. Tenth percentile

c. Third quartile d. All of the above. 12. Consider the following data: The height in centimetres of children in a third-grade class. Which of the following best describes these data? a. Attribute data b. Qualitative data c. Quantitative data

d. Sample data 13. A company has developed a new battery, but the average lifetime is unknown. In order to estimate this average, a sample of 100 batteries is tested and the average lifetime of this sample is found to be 250 hours. The 250 hours is the value of a: a. Parameter

b. Statistic c. Sampling frame d. Population. 14. A sample space is composed of three outcomes, called A, B and C. Outcome A is twice as probable as B, and B is twice as probably as C. The probabilities of A, B and C would be:

a. P(A) = 0.57, P(B) = 0.286, P(C) = 0.143 b. P(A) = 0.5, P(B) = 0.33, P(C) = 0.167 c. P(A) = 0.4, P(B) = 0.4, P(C) = 0.2

d. None of the above. 15. Suppose A and B are independent events of a sample space S with P(A) = 0.30 and P(B) = 0.50, then P(A n B) is a. 0.80 b. 0.60 c. 0.20 d. 0.15 16. The measure most affected by extreme values is the: a. Mean b. Second quartile

c. First quartile d. Interquartile range 17. The difference between the largest and smallest values in an ordered array is called the:

a. Standard deviation b. Variance c. Mean d. Range 18. Which of the following would not be a continuous random variable?

a. Age of student upon graduation from college b. Number of attempts to make a field goal in football c. Number of miles driven on a trip

d. Body temperature. 19. Which of the following is a correct statement? a. The mean is a measure of the deviation in a data set b. The standard deviation is a measure of dispersion

c. The range is a measure of central tendency d. The median is a measure of dispersion. 20. If A and B are events of a sample space S with A and B mutually exclusive, then P(A) + P(B): a. Must equal to 1 b. Could equal to 1 c. Would equal to P(A).P(B)

d. Greater than 1 PART B (Short answers- 60 marks) Answer ALL questions clearly showing all workings. QUESTION 1 (10 marks) An advertising executive is studying television viewing habits of married men and women during prime time hours. On the basis of past viewing records, the executive has determined that during prime time, husbands are watching television 60% of the time. It has also been determined that for 24% of prime time, the husband and wife are both watching, and that neither is watching 28% of the time.

(a) Copy the table below into your script book and fill in the blanks to provide a contingency table of probabilities for husbands and wives watching prime time television. (H = husband watching, and W = wife watching) (5 Marks) H _ H Total: W _ W Total: (b) During prime time:

(i) Find the probability that the wife is watching television. (1 Mark) (ii) Find the probability that given the husband is watching television, the wife is also watching television. (1 Mark)

(iii) Find the probability that both the Husband and wife are not watching television. (1 Mark) (c) Are the events H and W independent? Comment briefly. (2 Marks)