bus stats

bus_stat.xlsx

z-score

Consider a sample with data values of 10, 20, 12, 17, and 16. Compute the z-score for each of the five observations. (2.5 points)
x	z
10
20
12
17
16

Consider a sample with a mean of 30 and a standard deviation of 5.
Use Chebyshev's theorem to determine the percentage of the data within each of the following ranges: (2.5 points)
	%
a. 20 to 40
b. 15 to 45
c. 22 to 38
d. 18 to 42
e. 12 to 48

Suppose the data have a bell-shaped distribution with a mean of 30 and a standard deviation of 5.
Use the emperical rule to determine the percentage of the data within each of the following ranges: (1.5pts)
	%
a. 20 to 40
b. 15 to 45
c. 25 to 35

The mean retail price per gallon of gasoline was $2.81 with a standard deviation of $0.10, and the distribution of the prices is bell-shaped.
Determine the percentage of gasoline sold between each of the following prices: (1.5ps)
	%
a. $2.71 and $2.91
b. $2.71 and $3.01
c. more than $3.01

Suppose that the mean price of a backyard structure is $3100 and that the standard deviation is $1200.

Answer each of the following questions: (2.5pts)

a. What is the z-score for a structure costing $2300?

b. What is the z-score for a structure costing $4900?

c. Interpret the z-scores in parts a. and b. Comment on whether either should be considered an outlier.

d. If the cost of a structure is $13,000, should this be considered an outlier? Explain.

Data showing the average ticket price for a sample of 14 NFL teams are shown below.		(0.5pts each)
a. What is the mean ticket price?
b. If the previous year's mean ticket price was $72.20, what was the percentage increase in the mean ticket price over the one-year period?
c. Compute the median ticket price.
d. Compute the first and third quartiles.
e. Compute the standard deviation.
f. What is the z-score for the Dallas Cowboys ticket price? Should this be considered an outlier? Explain.
Team	Ticket Price
Atlanta Falcons	72
Buffalo Bills	51
Carolina Panthers	63
Chicago Bears	88
Cleveland Browns	55
Dallas Cowboys	160
Denver Broncos	77
Green Bay Packers	63
Indianapolis Colts	83
New Orleans Saints	62
New York Jets	87
Pittsburgh Steelers	67
Seattle Seahawks	61
Tennessee Titans	61

a. Provide the five-number summary for the data below. (2pts)
b. Show the box plot for the data. (1pt)
27
25
20
15
30
34
28
25

A data set has a first quartile of 42 and a third quartile of 50.

a. Compute the lower and upper limits for the corresponding box plot. (1pt)

b. Should a data value of 65 be considered an outlier? (1pt)

Five observations taken for two variables follow.
a. Develop a scatter diagram with x on the horizontal axis. (0.5 pt)
b. What does the scatter diagram indicate about the relationship between the two variables? (0.5 pt)
c. Compute are interpret the sample covariance. (1pt)
d. Compute and interpret the sample correlation coefficient. (1pt)
x	y
4	50
6	50
11	40
3	60
16	30

a. Develop a scatter diagram with x on the horizontal axis. (0.5 pt)
b. What does the scatter diagram indicate about the relationship between the two variables? (0.5 pt)
c. Compute are interpret the sample covariance. (1pt)
d. Compute and interpret the sample correlation coefficient. (1pt)
x	y
6	6
11	9
15	6
21	17
27	12

The daily high and low temperature for 14 cities around the world are shown below.
a. What is the mean high temperature? (0.5pt)
b. What is the mean low temperature? (0.5pt)
c. What is the correlation between the high and low temperatures? (0.5pt)
City	High	Low
Athens	68	50
Beijing	70	49
Berlin	65	44
Cairo	96	64
Dublin	57	46
Geneva	70	45
Hong Kong	80	73
London	67	45
Moscow	44	29
Paris	69	44
Rio de Janeiro	76	69
Rome	69	51
Tokyo	70	58
Toronto	44	39

Compute the weighted mean. (2pts)
xi	weight wi
3.2	6
2	3
2.5	2
5	8

Consider the sample data in the following frequency distribution.
a. Compute the sample mean. (1pt)
b. Compare the sample variance and the sample standard deviation. (2pts)
Class	Midpoint	Frequency
3 to 7	5	4
8 to 12	10	7
13 to 17	15	9
18 to 22	20	5

Use the sample responses below to compute the weighted mean for the business school and the corporate recruiters.(2pts)
Quality Assessment	Business School	Corporate Recruiters
5	44	31
4	66	34
3	60	43
2	10	12
1	0	0

The following frequency distribution shows the price per share of the 30 companies in the Dow Jones.
Compute the mean price per share and standard deviaiton of the price per share for ethe Dow Jones.(2pts)
Price per Share(in $)	Number of Companies
0 to 9	4
10 to 19	5
20 to 29	7
30 to 39	3
40 to 49	4
50 to 59	4
60 to 69	0
70 to 79	2
80 to 89	0
90 to 99	1