Assignment:
Q1: A company executive has read with interest the finding that the average U.S. office worker receives 36 e-mails per day. Assume that an executive, wishing to replicate this study within her own corporation, directs information technology personnel to find out the number of e-mails each of a sample of 100 office workers received yesterday, with the results as provided in the data file XR02019. Generate a data array and a frequency distribution describing this information and comment on whether any workers appeared to be receiving an especially high or low number of e-mails.
Q2: Construct a stem-and-leaf display for the following data:
Exercises
11 22 28 32 41 46 52 56 59
13 24 28 33 41 46 52 57 60
17 24 29 33 42 46 53 57 61
19 24 30 37 43 48 53 57 61
19 26 30 39 43 49 54 59 63
Q3: In the following stem-and-leaf display for a set of two-digit integers, the stem is the 10's digit, and each leaf is the 1's digit. What is the original set of data?
2_002278
3_011359
4_1344
5_47
Q4: Using the frequency distribution below, convert the information to a "less-than" ogive.
Annual Sales (Thousands)
Farms
Annual Sales (Thousands)
Under $10,000 963
$10,000-under $25,000 274
$25,000-under $50,000 171
$50,000-under $100,000 158
$100,000-under $250,000 189
$250,000-under $500,000 88
$500,000-under $1,000,000 43
$1,000,000 or more 26
Q5: Plywood, Inc. reported these returns on stockholder equity for the past 5 years: 4.3, 4.9, 7.2, 6.7, and 11.6. Consider these as population values.
a. Compute the range, the arithmetic mean, the variance, and the standard deviation.
Q6: The annual incomes of the five vice presidents of TMV Industries are: $125,000; $128,000; $122,000; $133,000; and $140,000. Consider this a population.
b. What is the range?
c. What is the arithmetic mean income?
d. What is the population variance? The standard deviation?
e. The annual incomes of officers of another firm similar to TMV Industries were also studied. The mean was $129,000 and the standard deviation $8,612. Compare the means and dispersion in the two firms.