Category: Mathematics homework help

a standard walker

Does talking while walking slow you down? Suppose a study considered mean cadence (steps per minute) for subjects using no walking device, a standard walker, and a rolling walker. In addition, the cadence was measured when the subjects had to perform dual tasks. The second task was to respond vocally to a signal or respond to an interview question while walking. Cadence was measured for subjects who were just walking (using no walking device, a standard walker, or a rolling walker), for subjects required to respond to a signal, and for subjects required to respond to an interview question while walking. How many cells are there in the data table?

[removed] a. 9
[removed] b. 8
[removed] c. 7
[removed] d. 12
[removed] e. 1

a car insurance company

Jim has a 5-year-old car in reasonably good condition. He wants to take out a $50,000 term (that is, accident benefit) car insurance policy until the car is 10 years old. Assume that the probability of a car having an accident in the year in which it is x years old is as follows:

x = age 5 6 7 8 9
P(accident) 0.01182 0.01282 0.01386 0.01513 0.01602

Jim is applying to a car insurance company for his car insurance policy. Using the probabilities that the car will have an accident in its 5th, 6th, 7th, 8th, or 9th year, and the $50,000 accident benefit, what is the expected loss to Car Insurance Company for the respective years? Round your answers to the nearest dollar.

[removed] a. $591, $641, $693, $747, $801
[removed] b. $591, $646, $693, $747, $801
[removed] c. $591, $641, $693, $757, $801
[removed] d. $581, $641, $693, $747, $801
[removed] e. $581, $646, $693, $757, $801

an archaeological study area

Wind Mountain is an archaeological study area located in southwestern New Mexico. Potsherds are broken pieces of prehistoric Native American clay vessels. One type of painted ceramic vessel is called Mimbres classic black-on-white. At three different sites the number of such sherds was counted in local dwelling excavations.

Site I Site II Site III
51 34 18
46 46 22
57 53 44
44 59 23
18   61
33   40
15    

Shall we reject or not reject the claim that there is no difference in population mean Mimbres classic black-on-white sherd counts for the three sites? Test given a = 0.01.
Find (or estimate) the P-value of the sample test statistic.

[removed] a. P-Value = 0.01
[removed] b. 0.05 < P-Value < 0.1
[removed] c. P-Value = 0.05
[removed] d. P-Value > 0.1
[removed] e. 0.01 < P-Value < 0.05

4 points   

The Last Cowboys

How long did real cowboys live? One answer may be found in the book The Last Cowboys by Connie Brooks (University of New Mexico Press). This delightful book presents a thoughtful sociological study of cowboys in West Texas and Southeastern New Mexico around the year 1890. Assume that a sample of 32 cowboys gave the following years of longevity:

59 52 67 86 72 66 99 89 84 91 91
92 69 68 87 86 73 61 71 75 72 73
85 84 91 57 77 76 84 93 58 49  

Make a stem-and-leaf display for these data.

[removed] a. 4 9 = 49 years
4 9
5 9 8 7 2
6 9 8 7 6 1
7 7 6 5 3 3 2 2 1
8 9 7 6 6 5 4 4 4
9 9 9 3 2 1 1 1
[removed] b. 4 9 = 49 years
4 9
5 2 7 8 9
6 1 6 7 8
7 1 2 2 3 3 5 7 8
8 3 4 4 5 6 6 7 9
9 1 1 1 2 3 9 9
[removed] c. 4 9 = 49 years
4 9
5 9 8 7 2
6 8 7 6 1
7 8 6 5 4 3 2 2 1
8 9 7 6 6 5 4 4 3
9 9 9 3 2 1 1 1
[removed] d. 4 9 = 49 years
4 9
5 2 7 8 9
6 1 6 7 8 9
7 1 2 2 3 3 5 6 7
8 4 4 4 5 6 6 7 9
9 1 1 1 2 3 9
[removed] e. none of these choices

Into what quartile does this rate fall?

What percentage of the general U.S. population have bachelor’s degrees? Suppose that the Statistical Abstract of the United States, 120th Edition, gives the following percentage of bachelor’s degrees by state. For convenience, the data are sorted in increasing order.

17 18 18 18 19 20 20 20 21 21
21 21 21 22 22 22 22 22 23 23
24 24 24 24 24 25 25 25 25 26
26 26 26 26 26 27 27 27 28 28
28 29 29 31 31 32 32 34 35 38

Illinois has a bachelor’s degree percentage rate of about 18%. Into what quartile does this rate fall?

[removed] a. second quartile
[removed] b. first quartile
[removed] c. third quartile
[removed] d. first quartile as well as second quartile
[removed] e. none of these choices

insurance claims to be processed

Assume that about 30% of all U.S. adults try to pad their insurance claims. Suppose that you are the director of an insurance adjustment office. Your office has just received 140 insurance claims to be processed in the next few days. What is the probability that from 45 to 47 of the claims have been padded?

[removed] a. 0.167
[removed] b. 0.119
[removed] c. 0.104
[removed] d. 0.056
[removed] e. 0.222

customer chosen at random

Are customers more loyal in the East or in the West? The following table is based on information from Trends in the United Sates, published by the food marketing Institute, Washington, D.C. The columns represent loyalty (in years) at a primary supermarket. The rows represent regions of the United States.

  Less Than

1 Year 

 1 – 2

Years

 3 – 4 Years 5 – 9 Years 10 – 14 Years 15 or More Years Row Total
East 32 54 59 112 77 118 452
Midwest 31 68 68 120 63 173 523
South 53 92 93 158 106 158 660
West 41 56 67 78 45 86 373
Column Total 157 270 287 468 291 535 2008

What is the probability that a customer chosen at random has been loyal 5 or more years given that he or she is from the South? Round your answer to the nearest thousandth.

[removed] a. 0.210
[removed] b. 0.326
[removed] c. 0.639
[removed] d. 0.417
[removed] e. none of these choices

regression analysis for a random sample

The systolic blood pressure of individuals is thought to be related to both age and weight. Let the systolic blood pressure, age, and weight be represented by the variables x1, x2, and x3, respectively. Suppose that Minitab was used to generate the following descriptive statistics, correlations, and regression analysis for a random sample of 15 individuals.

Descriptive Statistics
Variable N Mean Median TrMean StDev SE Mean
x1 15 155.56 156.06 155.56 3.815 0.985029
x2 15 63.42 64.02 63.42 1.226 0.316552
x3 15 195.04 194.64 195.04 4.164 1.075140

 

Variable Minimum Maximum Q1 Q3
x1 126 179 144.445 165.050
x2 42 83 47.888 77.461
x3 120 250 139.698 222.040

 

Correlations (Pearson)
  x1 x2
x2 0.870  
x3 0.802 0.517

Regression Analysis

The regression equation is
x1 = 0.804 + 1.308x2 + 0.966x3 

 

Predictor Coef StDev T P
Constant 0.804 0.692 1.16 0.134
x2 1.308 0.732 1.79 0.050
x3 0.966 0.705 1.37 0.098
S = 0.319 R-sq = 90.6 % R-sq(adj) = 92.6 %    

Relative to its mean, which variable has the smallest spread of data values?

a.       X1

b.      X2

c.       X3

4 points   

systolic blood pressure

The systolic blood pressure of individuals is thought to be related to both age and weight. Let the systolic blood pressure, age, and weight be represented by the variables x1, x2, and x3, respectively. Suppose that Minitab was used to generate the following descriptive statistics, correlations, and regression analysis for a random sample of 15 individuals.

Descriptive Statistics
Variable N Mean Median TrMean StDev SE Mean
x1 15 159.35 159.65 159.35 3.401 0.878134
x2 15 72.77 73.77 72.77 1.722 0.444618
x3 15 185.90 185.20 185.90 4.266 1.101476

 

Variable Minimum Maximum Q1 Q3
x1 126 173 140.497 166.049
x2 45 89 47.721 78.484
x3 129 249 140.492 222.010

 

Correlations (Pearson)
  x1 x2
x2 0.848  
x3 0.817 0.634

Regression Analysis

The regression equation is
x1 = 0.703 + 1.388x2 + 0.907x3 

 

Predictor Coef StDev T P
Constant 0.703 0.495 1.42 0.091
x2 1.388 0.669 2.07 0.030
x3 0.907 0.390 2.33 0.019
S = 0.424 R-sq = 92.5 % R-sq(adj) = 91.1 %    

Test the coefficient of  in the regression equation to determine if it is zero or not zero. Use a level of significance of 5%.  Do you accept or reject the null hypothesis that the coefficient should equal zero?

[removed] a. accept
[removed] b. reject

a strict distinction between nurses and domestic servants

What was the age distribution of nurses in Great Britain at the time of Florence Nightingale? Thanks to Florence Nightingale and the British census of 1851, we have the following information (based on data from classic text Notes on Nursing, by Florence Nightingale). Note: In 1851 there were 25,466 nurses in Great Britain. Furthermore, Nightingale made a strict distinction between nurses and domestic servants. Find the probability that a British nurse selected at random in 1851 would be 70 years of age or older. Round your answer to nearest thousandth.

Age range (yr) 20–29 30–39 40–49 50–59 60–69 70–79 80+
Midpoint (x) 24.5 34.5 44.5 54.5 64.5 75.5 84.5
Percent of nurses 5.7% 9.7% 19.5% 29.2% 25.0% 9.1% 1.8%
[removed] a. 0.091  
[removed] b. 0  
[removed] c. 0.099  
[removed] d. 0.105  
[removed] e. 0.109