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Question 1 Your answer is CORRECT. Which of the following is a measure of spread? a) median b) mode c) standard deviation d) third quartile e) mean Question 2 Your answer is CORRECT. a) 0. b) 0. c) 0. d) 0. e) 0. Question 3 Your answer is CORRECT. A service center receives an average of 0.8 customer complaints per hour. Management's goal is to receive fewer than three complaints each hour. Assume the number of complaints follows the Poisson distribution. Determine the probability that exactly four complaints will be received during the next eight hours. a) 0. Given that P (A) = 0.27, P (B) = 0.43, and P (A ∩ B) = 0.11 , find P (B | A). P(B|A) = P( A∩B)/P(A) P(B|A) = 0.11/0. P(B|A) = 0. Standard Deviation
b) 0. c) 0. d) 0. e) 0. Question 4 Your answer is CORRECT. The following table displays the results of a sample of 100 in which the subjects indicated their favorite ice cream of three listed. The data are organized by favorite ice cream and age group. What is the probability that a person chosen at random will be under 20 years old if he or she favors chocolate? Age Chocolate Vanilla Strawberry Over 40 12 8 10 20-40 15 8 12 Under 20 11 16 8 a) b) c) d) e) Question 5 Your answer is CORRECT. Suppose that in a large metropolitan area, 81% of all households have cable tv. Suppose you are interested in selecting a group of six households from this area. Let X be the number of households in a group of six households from this area that have cable tv. For what proportion of groups will at most two of the households have cable tv? a) 0. b) 0.
pbinom(2,6,0.81) [1] 0.
of under 20 years(chocolate) /Total (chocolate)
11/ dpois(4,0.8*8) [1] 0.
a) Two sample^ z^ test for means b) Two sample^ z^ test for proportions c) One sample^ t^ test for means d) One sample^ z^ test for means e) Matched pairs^ t^ test for means f) One sample^ z^ test for proportions g) Two sample^ t^ test for means Question 9 Your answer is CORRECT. The weights of male and female students in a class are summarized in the following boxplots: Which of the following is NOT correct? a) The median weight of the male students is about 166 lbs. b) About 50% of the male students have weights between 150 and 185 lbs. c) The mean weight of the female students is about 120 because of symmetry. d) The male students have less variability than the female students. Question 10 Your answer is CORRECT. Data for gas mileage (in mpg) for different vehicles was entered into a software package and part of the ANOVA table is shown below: Source DF SS MS Vehicle 6 505 84. Error 21 321 15. Total 27 826 One with larger scale will have less variability so : The male students have less variability than the female students Two sample z test for proportions
Determine the p-value for the data. a) 0. b) 0. c) 0. d) 0. e) 0. Question 11 Your answer is CORRECT. A random sample of 144 cans of fruit nectar is drawn from among all cans produced in a run. Prior experience has shown that the distribution of the contents has a mean of 13.22 ounces and a standard deviation of 2.16 ounce. What is the probability that the average contents of the 144 sample cans is less than 13.00 ounces? a) 0. b) 0. c) 0. d) 0. e) 0. Question 12 Your answer is CORRECT. If the P -value is larger than the level of significance α, then the researcher should __________ at level α. a) Reject H 0 b) Accept H 0 c) Fail to reject H 0 Question 13 Your answer is INCORRECT. For a specific location in a particularly rainy city, the time a new thunderstorm begins to produce rain (first drop time) is uniformly distributed throughout the day and independent of this first drop time for the if p value is greater than 0.05 (alpha) than it is fail to reject (FRHo) pnorm(13.00,13.22,2.16/sqrt(144)) [1] 0. pf(84.17/15.29,6,21, lower.tail=FALSE) [1] 0.
d) e) f) Cannot be determined. Question 16 Your answer is CORRECT. This is a written question, worth 11 points. DO NOT place the problem code on the answer sheet. A proctor will fill this out after exam submission. Show all steps (work) on your answer sheet for full credit. Problem Code: 1633 A person's muscle mass is expected to decrease with age. To explore this relationship in women, a nutritionist randomly selected 60 women aging from age 40 to 79 and measured their muscle mass. Using age as the explanatory variable and the muscle mass as the dependent variable, computer output of the data is as follows (the p-values are intentionally left blank): Predictor Coef StDev T P Constant 101.50 5.85 17.35 --- Age − 0.27 0.09 − 3.00 --- Part a: What is the regression equation? Part b: Calculate the 99% confidence interval of the slope of the regression line. Part c: Use the information provided to test whether there is a significant relationship between a person's age and muscle mass at the 5% level. a) I have placed my work and my answer on my answer sheet. b) I want to have points deducted from my test for not working this problem. Question 17 Your answer is CORRECT. This is a written question, worth 11 points. DO NOT place the problem code on the answer sheet. A proctor will fill this out after exam submission. Show all steps (work) on your answer sheet for full credit. Problem Code: 1723 Suppose the random variable has CDF given by the function
X
Part a: Find. Part b: Find the desity function. Part c: Find. Part d: Find. a) I have placed my work and my answer on my answer sheet. b) I want to have points deducted from my test for not working this problem. Question 18 Your answer is CORRECT. This is a written question, worth 11 points. DO NOT place the problem code on the answer sheet. A proctor will fill this out after exam submission. Show all steps (work) on your answer sheet for full credit. Problem Code: 1891 Employers would like to know which days of week employees are absent in a six-day work week. Previously employers believed that employees were absent equally during the week. Suppose a random sample of 60 managers were asked on which day of the week they had the highest number of employee absences. The results were distributed as in the table below. For the population of employees, do the days of highest number of absences occur with EQUAL frequencies during a six-day work week? Test at 5% significance level. Monday Tuesday Wednesday Thursday Friday Saturday 12 10 5 8 13 12 Part a: What type of test should be used in this situation? Part b: State the hypothesis. Part c: What is the test statistic? Part d: Find the p-value and state your conclusion. a) I have placed my work and my answer on my answer sheet. b) I want to have points deducted from my test for not working this problem. Question 19
F (x) =
x
3
x < 0
0 ≤ x ≤ 3
x > 3
P ( 1 ≤ X ≤ 2 )
f(x)
E[X]
V [X]
