Exam (elaborations) MATH 225N Week 8 Statistics Final Exam 2021

Exam (elaborations) MATH 225N Week 8 Statistics Final Exam 2021 Week 8 Final Examscored 128 out of 160= 80% QUESTION 1 Of the following pairs of events, which pair has mutually exclusive events? rolling a sum greater than 7 from two rolls of a standard die and rolling a 4 for the first throw drawing a 2 and drawing a 4 with replacement from a standard deck of cards rolling a sum of 9 from two rolls of a standard die and rolling a 2 for the first roll drawing a red card and then drawing a black card with replacement from a standard deck of cards QUESTION 2 Hugo averages 41 words per minute on a typing test with a standard deviation of 7.5 words per minute. Suppose Hugo's words per minute on a typing test are normally distributed. Let X= the number of words per minute on a typing test. Then, X∼N(41,7.5). Suppose Hugo types 45 words per minute in a typing test on Wednesday. The z-score when x=45 is ________. This z-score tells you that x=45 is ________ standard deviations to the ________ (right/left) of the mean, ________. Correctly fill in the blanks in the statement above. Select the correct answer below: Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is −0.533. This z-score tells you that x=45 is 0.533 standard deviations to the left of the mean, 41. Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is −0.381. This z-score tells you that x=45 is 0.381 standard deviations to the left of the mean, 41. Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is 0.381. This z-score tells you that x=45 is 0.381 standard deviations to the right of the mean, 41. MATH 225N Week 8 Statistics Final Exam zscore when x=45 is 0.533. This z-score tells you that x=45 is 0.533 standard deviations to the right of the mean, 41. QUESTION 3 A fitness center claims that the mean amount of time that a person spends at the gym per visit is 33 minutes. Identify the null hypothesis, H0, and the alternative hypothesis, Ha, in terms of the parameter μ. Select the correct answer below: H0: μ≠33; Ha: μ=33 H0: μ=33; Ha: μ≠33 H0: μ≥33; Ha: μ33 H0: μ≤33; Ha: μ33 QUESTION 4 A recent study suggested that 81% of senior citizens take at least one prescription medication. Amelia is a nurse at a large hospital who would like to know whether the percentage is the same for senior citizen patients who go to her hospital. She randomly selects 59 senior citizens patients who were treated at the hospital and finds that 49 of them take at least one prescription medication. What are the null and alternative hypotheses for this hypothesis test? {H0:p=0.81Ha:p0.81 {H0:p≠0.81Ha:p=0.81 {H0:p=0.81Ha:p0.81 {H0:p=0.81Ha:p≠0.81 QUESTION 5 A doctor notes her patient's temperature in degrees Fahrenheit every hour to make sure the patient does not get a fever. What is the level of measurement of the data. nominal ordinal interval ratio QUESTION 6 Assume the null hypothesis, H0, is: Jacob earns enough money to afford a luxury apartment. Find the Type I error in this scenario. Jacob thinks he does not earn enough money to afford the luxury apartment when, in fact, he does. Jacob thinks he does not earn enough money to afford the luxury apartment when, in fact, he does not. Jacob thinks he earns enough money to afford the luxury apartment when, in fact, he does not. Jacob thinks he earns enough money to afford the luxury apartment when, in fact, he does. QUESTION 7 The population standard deviation for the heights of dogs, in inches, in a city is 3.7 inches. If we want to be 95% confident that the sample mean is within 2 inches of the true population mean, what is the minimum sample size that can be taken? z0.101.282z0.051.645z0.0251.960z0.012.326z0.0052.576 Use the table above for the z-score, and be sure to round up to the nearest integer. ANSWER: 25 DOG HEIGHTS QUESTION 8 Alice sells boxes of candy at the baseball game and wants to know the mean number of boxes she sells. The numbers for the games so far are listed below. 16,14,14,21,15 Find the mean boxes sold. ANSWER: MEAN= 16 BOXES QUESTION 9 To test the effectiveness of a drug proposed to relieve symptoms of headache, physicians included participants for a study. They gave the drug to one group and a drug with no therapeutic effect to another group. Which group receives the placebo? the physicians the group that received the drug for headache the group that received the drug with no therapeutic effect all of the people in the study QUESTION 10 John owns a computer repair service. For each computer, he charges $50 plus $45 per hour of work. A linear equation that expresses the total amount of money John earns per computer is y=50+45x. What are the independent and dependent variables? What is the y-intercept and the slope? The independent variable (x) is the amount of time John fixes a computer. The dependent variable (y) is the amount, in dollars, John earns for a computer. John charges a one-time fee of $50 (this is when x=0), so the y-intercept is 50. John earns $45 for each hour he works, so the slope is 45. The independent