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math-225n-FINAL EXA math-225n-FINAL EXAM math-225n-FINAL EXAM

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2023/2024

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Download math-225n-FINAL EXAM and more Exams Nursing in PDF only on Docsity! 1 1/1 POINTS 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. That is correct! H0: μ≠33; Ha: μ=33 H0: μ=33; Ha: μ≠33 H0: μ≥33; Ha: μ<33 H0: μ≤33; Ha: μ>33 Answer Explanation Correct answer: Let the parameter μ be used to represent the mean. The null hypothesis is always stated with some form of equality: equal (=), greater than or equal to (≥), or less than or equal to (≤). Therefore, in this case, the null hypothesis H0 is μ=33. The alternative hypothesis is contradictory to the null hypothesis, so Ha is μ≠33. QUESTION 2 1/1 POINTS The answer choices below represent different hypothesis tests. Which of the choices are right-tailed tests? Select all correct answers. That is correct! H0:X≥17.1, Ha:X<17.1 H0: μ=33; Ha: μ≠33 2 H0:X=14.4, Ha:X≠14.4 H0:X≤3.8, Ha:X>3.8 H0:X≤7.4, Ha:X>7.4 H0:X=3.3, Ha:X≠3.3 Answer Explanation Correct answer: Remember the forms of the hypothesis tests. Right-tailed: H0:X≤X0, Ha:X>X0. Left-tailed: H0:X≥X0, Ha:X<X0. Two-tailed: H0:X=X0, Ha:X≠X0. H0:X≤3.8, Ha:X>3.8 H0:X≤7.4, Ha:X>7.4 5 Content attribution- Opens a dialog 6 QUESTION 4 1/1 POINTS Suppose a chef claims that her meatball weight is less than 4 ounces, on average. Several of her customers do not believe her, so the chef decides to do a hypothesis test, at a 10% significance level, to persuade them. She cooks 14 meatballs. The mean weight of the sample meatballs is 3.7 ounces. The chef knows from experience that the standard deviation for her meatball weight is 0.5 ounces. H0: μ≥4; Ha: μ<4 α=0.1 (significance level) What is the test statistic (z-score) of this one-mean hypothesis test, rounded to two decimal places? That is correct! $$Test statistic = −2.24 Answer Explanation Correct answers: $\text{Test statistic = }-2.24$Test statistic = −2.24 The hypotheses were chosen, and the significance level was decided on, so the next step in hypothesis testing is to compute the test statistic. In this scenario, the sample mean weight, x¯=3.7. The sample the chef uses is 14 meatballs, so n=14. She knows the standard deviation of the meatballs, σ=0.5. Lastly, the chef is comparing the population mean weight to 4 ounces. So, this value (found in the null and alternative hypotheses) is μ0. Now we will substitute the values into the formula to compute the test statistic: z0=x¯−μ0σn√=3.7−40.514√≈−0.30.134≈−2.24 So, the test statistic for this hypothesis test is z0=−2.24. QUESTION 5 7 1/1 POINTS What is the p-value of a right-tailed one-mean hypothesis test, with a test statistic of z0=1.74? (Do not round your answer; compute your answer using a value from the table below.) z1.51.61.71.81.90.000.9330.9450.9550.9640.9710.010.9340.9460.9560. 9650.9720.020.9360.9470.9570.9660.9730.030.9370.9480.9580.9660.9 730.040.9380.9490.9590.9670.9740.050.9390.9510.9600.9680.9740.06 0.9410.9520.9610.9690.9750.070.9420.9530.9620.9690.9760.080.9430. 9540.9620.9700.9760.090.9440.9540.9630.9710.977 That is correct! $$0.041 Answer Explanation Correct answers: $0.041$0.041 The p-value is the probability of an observed value of z=1.74 or greater if the null hypothesis is true, because this hypothesis test is right-tailed. This probability is equal to the area under the Standard Normal curve to the right of z=1.74. 10 In making the decision to reject or not reject H0, if α>p-value, reject H0 because the results of the sample data are significant. There is sufficient evidence to conclude that H0 is an incorrect belief and that the alternative hypothesis, Ha, may be correct. If α≤p-value, do not reject H0. The results of the sample data are not significant, so there is not sufficient evidence to conclude that the alternative hypothesis, Ha, may be correct. In this case, α=0.04 is less than or equal to p=0.0401, so the decision is to not reject the null hypothesis. QUESTION 7 1/1 POINTS 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? That is correct! {H0:p=0.81Ha:p>0.81 {H0:p≠0.81Ha:p=0.81 {H0:p=0.81Ha:p<0.81 {H0:p=0.81Ha:p≠0.81 Answer Explanation Correct answer: {H0:p=0.81Ha:p≠0.81 First verify whether all of the conditions have been met. Let p be the population proportion for the senior citizen patients treated at Amelia's hospital who take at least one prescription medication. 11 1. Since there are two independent outcomes for each trial, the proportion follows a binomial model. 2. The question states that the sample was collected randomly. 3. The expected number of successes, np=47.79, and the expected number of failures, nq=n(1−p)=11.21, are both greater than or equal to 5. Since Amelia is testing whether the proportion is the same, the null hypothesis is that p is equal to 0.81 and the alternative hypothesis is that p is not equal to 0.81. The null and alternative hypotheses are shown below. {H0:p=0.81Ha:p≠0.81 QUESTION 8 1/1 POINTS A researcher claims that the proportion of cars with manual transmission is less than 10%. To test this claim, a survey checked 1000 randomly selected cars. Of those cars, 95 had a manual transmission. The following is the setup for the hypothesis test: {H0:p=0.10Ha:p<0.10 Find the test statistic for this hypothesis test for a proportion. Round your answer to 2 decimal places. That is correct! $$Test_Statistic=−0.53 Answer Explanation Correct answers: $\text{Test_Statistic}=-0.53$Test_Statistic=−0.53 12 The proportion of successes is p^=951000=0.095. The test statistic is calculated as follows: 15 Answer Explanation Correct answers: $\text{P-value=}0.124$P-value=0.124 Here are the steps needed to calculate the p-value for a hypothesis test for a proportion: 1. Determine if the hypothesis test is left tailed, right tailed, or two tailed. 2. Compute the value of the test statistic. 3. If the hypothesis test is left tailed, the p-value will be the area under the standard normal curve to the left of the test statistic z0 If the test is right tailed, the p-value will be the area under the standard normal curve to the right of the test statistic z0 If the test is two tailed, the p-value will be the area to the left of −|z0| plus the area to the right of |z0| under the standard normal curve For this example, the test is a two tailed test and the test statistic, rounding to two decimal places, is z=0.1033−0.120.12(1−0.12)900−−−−−−−−−−−−√≈−1.54. Thus the p-value is the area under the Standard Normal curve to the left of a z-score of -1.54, plus the area under the Standard Normal curve to the right of a z-score of 1.54. z 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 -1.8 0.036 0.035 0.034 0.034 0.033 0.032 0.031 0.031 0.030 0.029 -1.7 0.045 0.044 0.043 0.042 0.041 0.040 0.039 0.038 0.038 0.037 -1.6 0.055 0.054 0.053 0.052 0.051 0.049 0.048 0.047 0.046 0.046 -1.5 0.067 0.066 0.064 0.063 0.062 0.061 0.059 0.058 0.057 0.056 -1.4 0.081 0.079 0.078 0.076 0.075 0.074 0.072 0.071 0.069 0.068 $$P-value=0.124 16 From a lookup table of the area under the Standard Normal curve, the corresponding area is then 2(0.062) = 0.124. 17 QUESTION 10 1/1 POINTS An economist claims that the proportion of people who plan to purchase a fully electric vehicle as their next car is greater than 65%. To test this claim, a random sample of 750 people are asked if they plan to purchase a fully electric vehicle as their next car Of these 750 people, 513 indicate that they do plan to purchase an electric vehicle. The following is the setup for this hypothesis test: H0:p=0.65 Ha:p>0.65 In this example, the p-value was determined to be 0.026. Come to a conclusion and interpret the results for this hypothesis test for a proportion (use a significance level of 5%.) That is correct! The decision is to reject the Null Hypothesis. The conclusion is that there is enough evidence to support the claim. The decision is to fail to reject the Null Hypothesis. The conclusion is that there is not enough evidence to support the claim. Answer Explanation Correct answer: The decision is to reject the Null Hypothesis. The conclusion is that there is enough evidence to support the claim. 20 1/1 POINTS Becky's statistics teacher was teaching the class how to perform the z-test for a proportion. Becky was bored because she had already mastered the test, so she decided to see if the coin she had in her pocket would come up heads or tails in a truly random fashion when flipped. She discretely flipped the coin 30 times and got heads 18 times. Becky conducts a one-proportion hypothesis test at the 5% significance level, to test whether the true proportion of heads is different from 50%. Which answer choice shows the correct null and alternative hypotheses for this test? That is correct! H0:p=0.6; Ha:p>0.6, which is a right-tailed test. H0:p=0.5; Ha:p<0.5, which is a left-tailed test. H0:p=0.6; Ha:p≠0.6, which is a two-tailed test. H0:p=0.5; Ha:p≠0.5, which is a two-tailed test. Answer Explanation Correct answer: H0:p=0.5; Ha:p≠0.5, which is a two-tailed test. The null hypothesis should be true proportion: H0:p=0.5. Becky wants to know if the true proportion of heads is different from 0.5. This means that we just want to test if the proportion is not 0.5. So, the alternative hypothesis is Ha:p≠0.5, which is a two- tailed test. 21 QUESTION 12 1/1 POINTS 22 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? That is correct! 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 variable (x) is the amount, in dollars, John earns for a computer. The dependent variable (y) is the amount of time John fixes a computer. John charges a one-time fee of $45 (this is when x=0), so the y-intercept is 45. John earns $50 for each hour he works, so the slope is 50. The independent variable (x) is the amount, in dollars, John earns for a computer. The dependent variable (y) is the amount of time John fixes 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 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 $45 (this is when x=0), so the y-intercept is 45. John earns $50 for each hour he works, so the slope is 50. 25 A scatterplot has a horizontal axis labeled Hours studying from 0 to 6 in increments of 1 and a vertical axis labeled Quiz score from 0 to 10 in increments of 2. The following points are plotted: left-parenthesis 1 comma 5 right-parentheses; left-parenthesis 2 comma 5 right-parentheses; left-parenthesis 3 comma 7 right-parentheses; left- parenthesis 4 comma 9 right-parentheses; left-parenthesis 5 comma 9 right- 26 parentheses. All values are approximate. 27 A scatterplot has a horizontal axis labeled Hours studying from 0 to 10 in increments of 2 and a vertical axis labeled Quiz score from 0 to 6 in increments of 1. The following points are plotted: left-parenthesis 5 comma 1 right-parentheses; left-parenthesis 5 comma 2 right-parentheses; left-parenthesis 7 comma 3 right-parentheses; left- parenthesis 9 comma 4 right-parentheses; left-parenthesis 9 comma 5 right- parentheses. All values are approximate. A scatterplot has a horizontal axis labeled Hours studying from 0 to 6 in increments of 1 and a vertical axis labeled Quiz score from 0 to 9 in increments of 1. The following points are plotted: left-parenthesis 1 comma 5 right-parentheses; left-parenthesis 2 comma 5 right-parentheses; left-parenthesis 3 comma 7 right-parentheses; left- parenthesis 4 comma 8 right-parentheses; left-parenthesis 5 comma 8 right- parentheses. 30 Video Games (Minutes) 306090120 Time with Family (Minutes) 504035 25 According to the line of best fit, the predicted number of minutes spent with family for someone who spent 95 minutes playing video games is 31.85. Is it reasonable to use this line of best fit to make the above prediction? That is correct! The estimate, a predicted time of 31.85 minutes, is unreliable but reasonable. The estimate, a predicted time of 31.85 minutes, is both unreliable and unreasonable. The estimate, a predicted time of 31.85 minutes, is both reliable and reasonable. The estimate, a predicted time of 31.85 minutes, is reliable but unreasonable. Answer Explanation Correct answer: The data in the table only includes video game times between 30 and 120 minutes, so the line of best fit gives reasonable predictions for values of x between 30 and 120. Since 95 is between these values, the estimate is both reliable and reasonable. QUESTION 15 0/1 POINTS Which of the following are feasible equations of a least squares regression line for the annual population change of a small country from the year 2000 to the year 2015? Select all that apply. The estimate, a predicted time of 31.85 minutes, is both reliable and reasonable. 31 That's not right. 32 yˆ=38,000+2500x yˆ=38,000−3500x yˆ=−38,000+2500x yˆ=38,000−1500x Answer Explanation Correct answer: Population change can be positive or negative, and it can increase or decrease. Based on the given information, there are no practical limits to population change, although there are limits such as the decrease in population cannot exceed the current population (as it would leave a negative number of people in the country), or the increase in population could be limited by other real-world factors (such as lack of space or legal immigration limits). Your answer: yˆ=38,000+2500x yˆ=38,000−1500x 35 $$r= 0.18 Answer Explanation Correct answers: $\text{r= }0.18$r= 0.18 The correlation coefficient can be calculated easily with Excel using the built-in CORREL function. 36 Weight Mileage 1. Open the accompanying data set in Excel. 2. In an open cell, type "=CORREL(A2:A31,B2:B31)", and then hit ENTER. You could label the result of this cell by writing "Correlation coefficient" or "r" in an adjacent open cell. The correlation coefficient, rounded to two decimal places, is r≈0.18. QUESTION 18 0/1 POINTS The weight of a car can influence the mileage that the car can obtain. A random sample of 20 cars’ weights and mileage is collected. The table for the weight and mileage of the cars is given below. Use Excel to find the best fit linear regression equation, where weight is the explanatory variable. Round the slope and intercept to three decimal places. 30.0 32.2 20.0 56.0 20.0 46.2 45.0 19.5 40.0 23.6 45.0 16.7 25.0 42.2 55.0 13.2 37 17.5 65.4 HelpCopy to ClipboardDownload CSV That's not right. 40 1/1 POINTS A farmer divided his piece of land into 4 equivalent groups. The quality of the soil is the same across the 4 groups of land. He planted the same crop in all 4 groups of land and recorded the yield of the crop in all 4 groups for a 4 week period. Is the study observational or experimental? If it is an experiment, what is the controlled factor? That is correct! The study is an observational study. The study is an experiment. The controlled factor is the 4 week observation period. The study is an experiment. The controlled factor is the land. The study is an experiment. The controlled factor is the growth of the crops. Answer Explanation Correct answer: The samples are chosen using an appropriate process; however, no attempt is made to control any aspect of the sample even though the variables of interest are recorded for each group. QUESTION 20 1/1 POINTS 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? That is correct! the physicians The study is an observational study. 41 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 Answer Explanation Correct answer: When the experimental units are people, applying treatments that should be inert can actually have effects. In this study, the drug with no therapeutic effects is the placebo, so the group that receives that drug receives the placebo. QUESTION 21 1/1 POINTS 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? That is correct! nominal ordinal interval ratio Answer Explanation Correct answer: interval This is interval data because degrees Fahrenheit is a numerical scale where differences are meaningful. However, because Fahrenheit does not have a true zero value, it is not ratio data. the group that received the drug with no therapeutic effect 42 QUESTION 22 0/1 POINTS As a member of a marketing team, you have been tasked with determining the number of DVDs that people have rented over the past six months. You sample twenty adults and decide that the best display of data is a frequency table for grouped data. Construct this table using four classes. 15,31,28,19,14,18,28,19,10,19,10,24,14,18,24,27,10,18,16,23 That's not right. Answer Explanation Lower Class Limit Upper Class Limit $$10 $$15 $$16 $$21 $$22 $$27 $$18 $$33 45 Lower Class Limit Upper Class Limit Frequency 10 16 22 28 To find the upper class limits, add the class width minus 1, to each lower class limit. For example, the upper class limit of the first class would be: 10+5=15. Lower Class Limit Upper Class Limit Frequency 10 15 16 21 22 27 28 33 To find the frequency for each class, count the number of data values that fall within the range of each class. For example, the data values 15, 14, 10, 10, 14, and 10 fall within the range of the first class, 10-15. So, the frequency of this class is 6. Lower Class Limit Upper Class Limit Frequency 10 15 6 16 21 7 22 27 4 46 28 33 3 QUESTION 23 1/1 POINTS The histogram below displays the weights of rainbow trout (in pounds) caught by all visitors at a lake on a Saturday afternoon. According to this histogram, which range of weights (in pounds) contains the lowest frequency? 47 A histogram has a vertical axis labeled Frequency and has a horizontal axis that measures six categories of rainbow trout weight (in pounds). Reading from left-to-right, the weight and frequency of each category are: 4.5 to 6.5 has frequency of 4, 6.5 to 8.5 has frequency 5, 8.5 to 10.5 has frequency 7, 10.5 to 12.5 has frequency 3, 12.5 to 14.5 has frequency 1, 14.5 to 16.5 has frequency 2. That is correct! $$greater than 12.5 but less than 14.5 Answer Explanation Correct answers: $\text{greater than }12.5\ \text{but less than }14.5$greater than 12.5 but less than 14.5 50 How many total students are in Ms. James's class? Do not include the units in your answer. 51 That is correct! $$23 Answer Explanation Correct answers: $23$23 To find the number of students in Ms. James's class, find the heights of the bars for that class and add them. In this case, we find it is 11+12=23. QUESTION 26 0/1 POINTS The line graph shown below represents the number of TVs in a house by square footage (in hundreds of feet). According to the information above, which of the following is an appropriate analysis of square footage and TVs? 52 A line graph has an x-axis labeled Square Footage (in hundreds of feet) in increments of one, and a y-axis labeled Number of TV's in increments of one. Beginning at the point start parentheses 6,2 end parentheses, a line increases to the point start parentheses 8.5,3 end parentheses. The line remains constant to the point start parentheses 10,3 end parentheses. The line then increases, passing through the point start parentheses 12,5 end parentheses and continues increasing until it reaches the point start parentheses 16,6 end parentheses. That's not right. From the data, the number of TVs doubled from a square footage of 8.5 and 10. From the data, there is a steady decrease in the square footage and number of TVs. From the data, there is a steady increase in the square footage and number of TVs. 55 Answer Explanation Correct answers: $\text{mode=}3\text{ cards}$mode=3 cards If we count the number of times each value appears in the list, we get the following frequency table: Value Frequency 3 3 5 2 10 1 11 1 12 2 Note that 3 occurs 3 times, which is the greatest frequency, so 3 is the mode of the number of cards drawn from a deck until a queen appears. QUESTION 30 1/1 POINTS Given the following histogram, decide if the data is skewed or symmetrical. $$mode=3 cards 56 A bar graph has a horizontal axis titled Values labeled from 2 to 18 in increments of 2 and a vertical axis titled Frequency labeled from 0 to 200 in increments of 50. 14 bars are plotted, above the numbers 2 to 16. From left to right, the heights of the bars are as follows: 1. 5. 10. 40, 75, 125, 190, 180, 130, 125, 60, 25,20, 10. All values are approximate. That is correct! The data are skewed to the left. The data are skewed to the right. The data are symmetric. Answer Explanation 57 Correct answer: The data are symmetric. Note that the histogram appears to be roughly symmetric. So the data are symmetric. QUESTION 31 1/1 POINTS Which of the data sets represented by the following box and whisker plots has the smallest standard deviation? Four horizontal box-and-whisker plots share a vertical axis with the classes D, C, B, and A and a horizontal axis from 0 to 120 in increments of 20. The box-and-whisker plot above the class label A has the following five-number summary: 44, 69, 77, 82, and 112. The box-and-whisker plot above the class label B has the following five-number summary: 19, 64, 78, 87, and 121. The box-and-whisker plot above the class label C has the following five-number summary: 60, 72, 75, 80, and 92. The box-and-whisker 60 The distribution that is the tallest and least spread out is B, so that has the smallest standard deviation. QUESTION 33 61 1/1 POINTS Brayden tosses a coin 500 times. Of those 500 times, he observes heads a total of 416 times. Calculations show that the probability of this occurring by chance is less than 0.01, assuming the coin is fair. Determine the meaning of the significance level. That is correct! We expect that 416 of every 500 coin tosses will result in heads. At the 0.01 level of significance, the coin is likely not a fair coin. There is certainty that the coin is not a fair coin. The results are not statistically significant at the 0.05 level of significance. Answer Explanation Correct answer: The results of the experiment are significant at the 0.01 level of significance. This means the probability that the outcome was the result of chance is 0.01 or less. Because of this, we can be fairly confident, but not certain, that the coin is not a fair coin. QUESTION 34 1/1 POINTS Is the statement below true or false? Independent is the property of two events in which the knowledge that one of the events occurred does not affect the chance the other occurs. At the 0.01 level of significance, the coin is likely not a fair coin. 62 That is correct! True 65 $$(67, 87) 66 Answer Explanation Correct answers: $\left(67,\ 87\right)$(67, 87) A confidence interval is an interval of values, centered on a point estimate, of the form (pointestimate−marginof error,pointestimate+marginof error) Using the given point estimate for the mean, x¯=77 and margin of error 10, the confidence interval is: (77−10,77+10)(67,87) QUESTION 38 1/1 POINTS A random sample of adults were asked whether they prefer reading an e-book over a printed book. The survey resulted in a sample proportion of p′=0.14, with a sampling standard deviation of σp′=0.02, who preferred reading an e-book. Use the empirical rule to construct a 95% confidence interval for the true proportion of adults who prefer e-books. That is correct! $$(0.10, 0.18) Answer Explanation Correct answers: $\left(0.10,\ 0.18\right)$(0.10, 0.18) By the Empirical Rule, a 95% confidence interval corresponds to a z-score of z=2. Substituting the given values p′=0.14 and σp′=0.02, a confidence interval is (p′−z⋅σp′,p′+z⋅σp′)(0.14−2⋅0.02,0.14+2⋅0.02)(0.14−0.04,0.14+0.04)(0.10,0. 67 18) 70 8 10 9 13 10 26 11 14 12 12 13 8 71 14 3 15 1 16 1 Value Frequency 12 1 13 1 14 3 15 6 16 23 17 29 18 19 19 15 20 3 Value Frequency 0 5 1 16 2 23 3 19 4 22 5 9 72 6 4 7 2 Answer Explanation Correct answer: 75 19 15 20 3 And the following is right skewed because of its concentration of small values with many larger values: Value Frequency 0 5 1 16 2 23 3 19 4 22 5 9 6 4 7 2 The other frequency tables are more balanced and symmetrical. Your answer: Value Frequency 5 1 6 3 7 8 8 10 9 13 10 26 11 14 12 12 13 8 14 3 76 15 1 16 1 The data in this table is roughly symmetrical about 10. 77 Value Frequency 12 1 13 1 14 3 15 6 16 23 17 29 18 19 19 15 20 3 Correct! QUESTION 41 1/1 POINTS A poll was conducted during the final game of the basketball season to determine whether fans wanted to see the defending champions win the game or the challenging team win the game. From the poll, 216 of the 374 residents sampled from urban areas want the defending champions to win the game. In more rural areas, 304 of the 466 residents polled want the defending champions to win the game. Assuming location has nothing to do with team preference, the probability that the data gathered was the result of chance is calculated to be 0.03. What is the correct interpretation of this calculation? That is correct! More people from rural areas want the defending champions to win the game. Exactly 216 out of every 374 urban residents want the defending champions to win the game. 80 True or False: The more shoes a manufacturer makes, the more shoes they sell. That is correct! True False Answer Explanation Correct answer: In supply and demand, a company doesn't make a product hoping that someone will buy them, they have a Demand first for their product and then, they produce more of that given product. QUESTION 45 1/1 POINTS Fill in the following contingency table and find the number of students who both do not play sports AND do not play an instrument. StudentsplaysportsdonotplaysportsTotalplayaninstrument33donotplaya ninstrument69Total6267 That is correct! $$34 Answer Explanation Correct answers: $34$34 By using the known totals along the rows and columns you can fill in the rest of the contingency table. For example, looking at the second row in the table, we know False 81 that 33 added to the unknown number in the middle is 67, so that unknown number is 34. Continuing in this way, we can fill in the entire table: StudentsplaysportsdonotplaysportsTotalplayaninstrument273360donot playaninstrument353469Total6267129 From this, we can see that the number of students who both do not play sports and do not play an instrument is 34. FEEDBACK Content attribution- Opens a dialog QUESTION 45 1/1 POINTS Fill in the following contingency table and find the number of students who both do not play sports AND do not play an instrument. StudentsplaysportsdonotplaysportsTotalplayaninstrument33donotplaya ninstrument69Total6267 That is correct! $$34 Answer Explanation Correct answers: $34$34 By using the known totals along the rows and columns you can fill in the rest of the contingency table. For example, looking at the second row in the table, we know that 33 added to the unknown number in the middle is 67, so that unknown number is 34. Continuing in this way, we can fill in the entire table: 82 StudentsplaysportsdonotplaysportsTotalplayaninstrument273360donot playaninstrument353469Total6267129 From this, we can see that the number of students who both do not play sports and do not play an instrument is 34. QUESTION 46 1/1 POINTS The answer choices below represent different hypothesis tests. Which of the choices are left-tailed tests? Select all correct answers. That is correct! H0:X=17.3, Ha:X≠17.3 H0:X≥19.7, Ha:X<19.7 H0:X≥11.2, Ha:X<11.2 H0:X=13.2, Ha:X≠13.2 85 Correct answer: A Type I error is the decision to reject the null hypothesis when it is true. In this case, the Type I error is when Jacob thinks he does not earn enough money when he really does. QUESTION 48 1/1 POINTS Given the plot of normal distributions A and B below, which of the following statements is true? Select all correct answers. A normal bell curve labeled Upper A and a normal elongated curve labeled Upper B are centered at the same point. Normal curve Upper B is narrower and above normal curve Upper A. That is correct! A has the larger mean. Jacob thinks he does not earn enough money to afford the luxury apartment when, in fact, he does. 86 87 B has the larger mean. The means of A and B are equal. A has the larger standard deviation. B has the larger standard deviation. The standard deviations of A and B are equal. Answer Explanation Correct answer: The means of A and B are equal. A has the larger standard deviation. 90 Suppose Hugo types 54 words per minute in a typing test on Wednesday. The z-score when x=54 is −1.5. This z-score tells you that x=54 is 1.5 standard deviations to the left of the mean, 72. Answer Explanation 91 Correct answer: The z-score can be found using the formula z=x−μσ=54−7212=−1812≈−1.5 A negative value of z means that that the value is below (or to the left of) the mean, which was given in the problem as μ=72 words per minute in a typing test. The z- score tells you how many standard deviations the value x is above (to the right of) or below (to the left of) the mean, μ. So, typing 54 words per minute is 1.5 standard deviations away from the mean. QUESTION 50 1/1 POINTS The following frequency table summarizes a set of data. What is the five-number summary? Value Frequency 1 4 2 2 7 1 8 1 9 1 10 4 12 3 16 1 20 1 22 1 Suppose Hugo types 54 words per minute in a typing test on Wednesday. The z-score when x=54 is −1.5. This z-score tells you that x=54 is 1.5 standard deviations to the left of the mean, 72. 92 That is correct! Min Q1 Median Q3 Max 1 2 10 12 22 Min Q1 Median Q3 Max 1 2 6 12 22 Min Q1 Median Q3 Max 1 4 5 10 22 Min Q1 Median Q3 Max 1 7 8 14 22 Min Q1 Median Q3 Max 1 3 14 14 22 Answer Explanation Correct answer: Min Q1 Median Q3 Max 1 2 10 12 22 We can immediately see that the minimum value is 1 and the maximum value is 22. If we add up the frequencies in the table, we see that there are 19 total values in the data set. Therefore, the median value is the one where there are 9 values below it and 9 values above it. By adding up frequencies, we see that this happens at the value 10, so that is the median.