Southern New Hampshire University - MAT-240 R1062 – 8-3 MySatLab: Final Exam

MAT-240 R1062 – 8-3 MySatLab: Final Exam This Question: 10 pts 1 of 28 (0 complete) w §• This Test: 280 pts possible { Question Help @ A concrete mix is designed to withstand 3000 pounds per square inch (psi) of pressure. The following data represent the strength of nine randomly selected casts psi) 3970, 4090, 3300, 3000. 2950. 3820. 4090, 4030, 3690 o Compute the mean, median and mode strength of the concrete (in psi). Compute the mean strength of the concrete. Select the correct choice below and. if necessary, fill in the answer box to complete your choice. ’- -’ A. The mean strength of the concrete is psi of pressure. (Round to the nearest tenth as needed.) ” ' B. The mean does not exist. Compute the median strength of the concrete. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. .’-*-’ A. The median strength of the concrete is psi of pressure. (Round to the nearest tenth as needed.) :' ” ' B. The median does not exist. Compute the mo de stren gth of the concrete SeIect the correct choice below and. if ne cess ary fill in the answer box to complete your choice ’: ’ A. The mode of the strengths of the concrete is psi of pressure. (Round to the nearest tenth as needed.) ' B. The mode does not exist. This Question: 10 pts g 2 of 28 (1 complete} V §• Compute the range and sample standard deviation for strength Df the concrete (in psi) 3960, 4130, 3100. 3100, 2960. 383D, 4130, 4060 The range is psi. s = psi (Round to one decimal place as needed.) This Question: 10 pts g 3 of 28 {2 complete} V $• Determine whether the random variable is discrete or continuous. In each case state the possible values of the random variable (aj The number of points scored during a basketball game. (b} The time it takes to fly from City A to City B. (a} Is the number of points scored during a basketball game discrete or continuous? '.”..' A. The random variable is continuous. The possible values are x Z 0. 'o.' B. The random variable is discrete. The possible values are x = 0 1 2 '” .' C. The random variable is Th+ possible values are x 2 0 '.._.' D. The random variable is continuous. The possible values are x = 0 1, 2 . (b} Is the time it takes to fly from CiTy A to City B discrete or continuous? '.”.' A. The random variable is continuous. The possible values are t = 1, 2. 3. '.”..' B. The random variable is discrete. The possible values are t 0. '” .' C. The random variable is Th+ possible values are I = 1. 2 '.+.' D. The random variable is continuous. The possible values are t 0 This Tes Determine the required value of the missing probability to make the distribution a discrete probability distribution P(4) = (Type an integer or a de x P(x) a 3 0.19 0.31 0.25 This Question: 10 pts 6 of 28 (5 complete) w §• This Test: 280 pts possible , Question Help @ a re a cor h nd to th €• eob bility’ sha' dd 39) ’t''buted with mean p = 50 and standard deviation a = 7. Co mpute the probab ilily. Be sure to drayy a norm al curve with the Click the icon to view a table of areas under the normal curve. Which of the following normal curves corresponds to P(X 39)? P(X 39) = 9420 {Round to four decimal places as needed. ) This Question: 10 pts Fill in the blanks to correctly complete the sentence below. g 7 of 28 (6 complete) w §• This Test: 280 pts possible • Question Help O Suppose a simple random sample of size n is drawn from a large population with mean p and standard deviation o. The sample distribution of x has mean y{ = and standard deviation o§ = Suppose a simple random sample of size n s drawn from a large population with mean p and standard deviation o. The sample distribution of x has mean y{ = and stand ard deviation oj = Describe the sampling distribution of p. Assume the size of the population is 25.000. n = 5D0, p = 0.5 Choose the phrase that best describes the shape of the sampling distribution of p below. '”” ! A. Not normal because n S 0.05N and np(1— p) 10. !•! B. Approximately normal because n S 0.05N and np(1 — p) Z 10 '”” ! C. Approximately normal because n 0.05N and np(1 — p) 10 !.”.! D. Not normal because n C 0.05N and np(1— p) z 10 Determine the mean of the sampling distribution of p. g• = (Round to one decimal place as needed ) Determine the standard deviation of the sampling distribution of p. o• = (Round to three decimal places as needed.) This Question: 10 pts g 9 of 28 (8 complete) V §• Compute the critical value z / 2 that corresponds to a 94% level of confidence z 2 = 1 (Round to two decimal places as needed.) This Question. 10 pts g 10 of 28 (9 complete) w $• Constru4 a confidence interval of the population proportion at the given level of confidence. x = 175 .n = 250. 90% confidence The 90’4 confidence interval is ( , ). (Use ascending Round to three decimal places as needed.) Determine the point estimate of the population mean and margin of errar far the confidence interval. Lower bound is 20. upper bound is 26 The point estimate af the population mean is The margin of error for the confidence interval is . This Question: 10 pts •§ 12 DI 28 (11 complete) w §• The following data represent the concentration of organic carbon collected from organic This Test: 280 pts possible •° Question Help @ soil. Construct a 99a confidence interv al for the mean concentration of dissolved organic 29.80 27.10 1651 5.30 carbon collected from organic soil. (Note: x = 17.7 mg/L and s = 8.22 mg/L) 17.50 20.46 1490 33.67 30.91 14.86 22.49 1535 9.72 Click the icon to view the table of areas under the t-distribution. 14.86 8.09 520 18.30 Construct a 99°â confidence interval for the mean concentration of dissolved org anic carb on collecte d from organic soil. ( 2 45 . 22 6 ) (Use ascending order. Round to tv/o decimal places as needed. ) This Question. 10 pts •$ 13 of 28 (12 complete) w $• This Suppose the null hypothesis is rejected. State the conclusion based on the results of the test. Six years ago, 11.99 of registered births were to teenage mothers. A sociologist believes that the percentage has decreased since then Which of the followin g is the correct conclusion? '..”.:' A. There is not suffici+nt evidence to conclude that the percentage of teenage mothers has remained the same '. ..' B. There is not sufficient evidence to conclude that the percentage of teenage mothers has decreased. 'o.' C. There is sufficient evidence to conclude tha the percentage of teenage mothers has decreased. '.”..' D. There is sufficient evidence to conclude that the percentage of teenage mothers has remained the same. Test the hypothesis using the P-value approach. Be sure to verify the requirements of the test. H0 : p = 0.5 versus H1. p D.ii n = 125; x = 73, o = 0.01 Is npç 1 — pç) 2 10? Use technology to find the P-value. P-value= (Round to three decimal places as D n e e the null hypothesis, because fhe P-value is Lhan o This Question: 10 pts •§ 15 of 28 (14 complete) w §• This Test: 280 pts possible } Question Help Researchers wanted to measure the effect of alcohol on the development of the hippocampal region in adolescents. The researchers randomly selected 13 adolescents viLh alcohol use disorders. They yyanted to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal volume of cmm . An analysis of fhe sample data revealed that the hippocampal volume is approximately normal with x = 8.22 and s = Conduct an appropriate test at the a = 0.05 level of significance. Choose the corrent hypotheses. Hç: H, : 9.02 9.02 Find the test stalistic. tç = 3 2 (Round to two decimal places as needed.) Find the P-value. The P-value is . (Round to three deómal places as needed.) What conclusion can be drawn’ ‹ › A. Do not reject Hy . There is not sullicient evidence to condude that the hippocampal volumes in the alcoholic adolescents are greater than the normal volume of 9.02 cm* . 3!) B Reject Hg . There is suficient evidence to conclude that the hippocampal volumes in the alcoholic adolescents are less than the normal volume of 9 02 cmm ‹ › C. Reject Hg . There is not sufficient evidence to conclude that the hippocampal volumes in the alcoholic adolescents are less than the normal volume of 9.02 ‹ › D. Do not reject Hg . There is sufficient evidence to con elude that the hippocampal volum es in the alcoholic a dalescents are greater than the normal volume of This Question: 10 pts 15 of 28 (27 complete) w §• This Test: 280 pts possible { Question Help O It has long been stated that the mean temperature of humans is 98.6’F. However two researchers currently involved in the subject thought that the mean temperature of humans is less than 98.6”F. They measured the temperatures of 148 healthy adults 1 to 4 times daily for 3 days, obtaining 600 measurements. The sample data resulted in a sample mean of 97.7”F and a sample standard deviation of 0.6°F. (a)Using the classical approach, judge whether the mean temperature of humans is less than 98.6'F at the a = 0.01 level of significance. (b)Approximate the P-value. @{ Click here to view the t-Distribution Area in Right Tail. (a) Choose the correct answer below. '..”..' A. Do not reject Hg since the test statistic is not less than the critical value. '.o.' B. Do not reject Hg since the test statistic is less than the critical value. ' ” ' C . Reject Hg since the test statistic is less than the critical value. '..”..' D. Reject Hg since the test statistic is not less than the critical value. (b) The P-value is approximately (Round to four decimal places as needed.) This Question: 10 pts •§ 17 of 28 (15 complete) w §• This Test. 280 pts possiDle { Question Help @ Determine whether the following sampling is dependent or independent. Indicate whether the response variable is qualitative or quantitative. A researcher wishes Io compare annual salaries of doctors and non- doctors. She obtains a random sample of 993 professionals of each category who work and determines each individual’s annual salary Determine whether the following sampling is dependent or independent. ” ' A. The sampling is dependent because an individual selected for one sample does not dictate which individual is to be in the second sample. ” ' B. The sampling is dependent because an individual selected for one sample does dictate which individual is to be in the second sample. '.*.' C . The sampling is independent because an individual selected for one sample does dictate which individual is to be in the second sample. ” ' D. The sampling is independent because an individual selected for one sample does not dictate which individual is to be in the second sample. Indicate wheth er the res p onse variable is qua lilative or quantitative . '.o.' A. The variable is quantitative because it is a numerical measure. ” ' B. The variable is qualitative because it is a numerical measure. ” ' C . The variable is qualitative because it classifies the individu ” ' D. The variable is quantitative because it classifies the individual. This Question: 10 pts g 1B Of 2B (16 complete) w §• This Test: 280 pts possible , Question Help O In randomized, double-blind clinical trials of a new vaccine, monkeys were randomly divided into two groups. Sub ects in grouo 1 received the new vaccine yhile subjects in group 2 received a control vaccine. After the first dose, 101 of 711 subjects in the experimental group (group 1) exoerienced fever as a side After the [ first dose, 72 of 612 of the subjects in the control group (group 2) experienced fever as a side effect. Construct a 95% confidence interval for the difference between — the two papulation pro portions. p1— o2 Use x1 = 101, n1 711 , xg = 72, and n2 = 612. The 95°d confidence interval for p1 — p2 is ( 0 2 , 0 ). (Use ascending Round to three decimal places as needed , This Question: 10 pts g 19 of 28 (17 complete) w §• This Test: 280 pts possible ,J question Heip O A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) and (b) below. Observation 1 2 3 4 S 6 s Date 1/2S 3/19 5/30 7/3 9/13 11/7 Initial SS.S 62 2 38.3 37.3 After five years 58.0 TO 9 42.1 (a) Why is it imponant to take the measurements on the same date? ' ” :' A. Those are the same dates that biologists use to take water clarity samples '.T..' B. ” :' C. ” :' D. Using the same dates maximizes the difference in water clarity (b) Does the evidence suggest that the clarity of the lake is improving at the a = 0.05 level of significance? Note that the normal probability plot and ooxplot of the data indicate that the diPerences are approximately normally distributed with no outliers. Choose the correct conclusion below. Reject H,. ' ' Do not reject Hi .