UST 404 STUDY GUIDE PROBLEMS

Use the data in the box below to calculate the range and variance.Note:For these exercises our calculations of variance will use N – 1 in the denominator.

1) Range:

2) Variance:

Find the range and variance for the following sets of data

Set A: 9, 6, 7, 4, 6, 4, 8, 7, 6, 3

3) Range:

4) Variance:

Set B: 9, 4, 18, 1, 16, 2, 17, 4, 15, 4

5) Range:

6) Variance:

Set C: 2, 30, 28, 5, 9, 20, 6, 11, 20, 9 (for this set calculate the standard deviation as well)

7) Range:

8) Variance:

9) Standard deviation:

For the table below, calculate the mode, mean, interquartile range and standard deviation.

10) Mode:

11) Mean:

12) Interquartile range:

13) Standard deviation:

Exercise 2

Remember, probability is always expressed as (p = .xx). Do not answer in percentage form if the question asks for probability.

1) What is the probability of rolling either a 5 or a 4 with a die that has nine sides

2) Four people are sitting on a couch. Two are wearing red shirts, one is wearing a blue shirt, and one is wearing a green shirt. What is the probability of a person with a red shirt being the next one to get up and walk out the door.

3) Seventeen people are sitting in a room. Fifteen of them are female, and two are male. If we randomly select two people (without replacement), what is the probability that they will be both female?

Use the table below to answer questions 4-6.

4) What is the probability of randomly selecting a respondent who claims to be “extremely conservative”?

5) What is the probability of randomly selecting a respondent who is more conservative than “moderate”?

6) What is the probability of randomly selecting two respondents, the first one being “moderate” and the second being extremely conservative”?

Suppose the city of Knoxville, Tennessee, has an average July temperature of 87 degrees (F) with a standard deviation of 4 degrees. This information was gathered over the past 100 years. Calculate the z-scores for the next two July temperatures if those temperatures are equal to the following (the mean and standard deviation do not change).

7) 84

8) 92

A normal distribution of the number of parking tickets BSG students receive in a typical semester shows a mean of 2.5 with a standard deviation of .6. Calculate the z-score for the number of parking tickets below.

9) 2 tickets

Two people, one in Los Angeles and one in New York, take the Graduate Record Entrance exam. These were different exams, but we would like to compare their scores. The person in Los Angeles received a 647 while the average was 640 with a standard deviation of 20. The person in New York received a 570 while the average was 560 with a standard deviation of 25. First, calculate the z-score for each person, then indicate who scored higher after standardizing the scores

10) Person 1 (los Angeles)

11) Person 2 (New York)

12) Which person scored higher, New York or, Los Angeles?

Suppose the college is trying to decide whether to build more parking lots on campus. They decide to count the number of cars in BSC parking lots at 2:00 in the afternoon. They count the number for 15 straight days and find the number of cars takes the shape of a normal distribution with a mean of 670 and a standard deviation of 49. By calculating the z-scores and using the z table, determine the following probabilities

13) A day with less than 624 cars

14) A day with less than 780