Question 1 of 25 1.0 PointsThe amount of time needed to run the Boston marathon is an example of whi

Question 1 of 25 1.0 PointsThe amount of time needed to run the Boston marathon is an example of which type of variable?A.continuousB.qualitativeC.discreteD.none of the aboveReset SelectionPart 2 of 9 -Question 2 of 25 1.0 PointsThe staff at a small company includes: 4 secretaries, 20 technicians, 4 engineers, 2 executives,and 50 factory workers. If a person is selected at random, what is the probability that he or sheis a factory worker?A.1/4B.2/5C.1/8D.5/8Reset SelectionQuestion 3 of 25 1.0 PointsThe formal way to revise probabilities based on new information is to use:A.conditional probabilitiesB.complementary probabilitiesC.common sense probabilitiesD.unilateral probabilitiesReset SelectionPart 3 of 9 -Question 4 of 25 1.0 PointsFind the variance of the following probability distribution.X P(X)1 0.102 0.203 0.354 0.305 0.05A.1.1B.1.21C.1.05D.1.02Reset SelectionQuestion 5 of 25 1.0 PointsThe following data were obtained from a survey of college students. The variable X represents the number of nonassignedbooks read during the past six months.x 0 1 2 3 4 5P (X=x) 0.20 0.25 0.20 0.15 0.10 0.10What is the expected value of X?A.2.0B.6.25C.1.20D.3.65Reset SelectionQuestion 6 of 25 1.0 PointsThe following data were obtained from a survey of college students. The variable X represents the number of nonassignedbooks read during the past six months.x 0 1 2 3 4 5P (X=x) 0.20 0.25 0.20 0.15 0.10 0.10Find P( X 3)A.0.20B.0.85C.0.15D.0.80Reset SelectionPart 4 of 9 -Question 7 of 25 1.0 PointsThe standard deviation of a probability distribution must be:A.a nonnegative numberB.a negative numberC.a number between 0 and 1D.less than the value of the meanReset SelectionQuestion 8 of 25 1.0 PointsThe mean of a probability distribution is a:A.measure of central locationB.measure of skewness of the distributionC.measure of variability of the distributionD.measure of relative likelihoodReset SelectionQuestion 9 of 25 1.0 PointsThe standard deviation of is usually called theA.randomized standard errorB.standard error of the sampleC.standard error of the populationD.standard error of the meanReset SelectionQuestion 10 of 25 1.0 PointsIf the value of the standard normal random variable Z is positive, then the original score iswhere in relationship to the mean?A.to the right of the meanB.equal to the meanC.to the left of the meanD.one standard deviation higher than the meanReset SelectionQuestion 11 of 25 1.0 PointsThe mean of a probability distribution can be:A.a positive numberB.a negative numberC.zeroD.all of the aboveReset SelectionQuestion 12 of 25 1.0 PointsThe average height of flowering cherry trees in a nursery is 11 feet. If the heights are normallydistributed with a standard deviation of 1.6, find the probability that a randomly selected cherrytree in this nursery is less than 13 feet tall.A. 0.67B.0.89C.0.95D.0.11Reset SelectionPart 5 of 9 -Question 13 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.A statistics professor has just given a final examination in his statistical inference course. He is particularlyinterested in learning how his class of 40 students performed on this exam. The scores are shown below.77 81 74 77 79 73 80 85 86 7383 84 81 73 75 91 76 77 95 7690 85 92 84 81 64 75 90 78 7882 78 86 86 82 70 76 78 72 93What is the mean score on this exam? Place your answer, rounded to two decimal places in the blank. Forexample, 65.78 would be a legitimate entry.Part 6 of 9 -Question 14 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.A DVD rental business determines that customers will rent X number of DVDs according to thefollowing distribution:Number of DVDs rented X 1 2 3 4 5Probability P(X) 0.15 0.25 0.3 0.25 0.05What is the mean number of DVDs that customers rent? Round your answer to one decimalplace as necessary. For example, 4.5 would be a legitimate entry.Answer: Question 15 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.Find the expected value of the following probability distribution.X 1 2 3 4 5P(X) 0.05 0.20 0.35 0.25 0.15Round your answer to two decimal place as necessary. For example, 4.56 would be a legitimateentry.Expected value =Part 7 of 9 -Question 16 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.Mothers Against Drunk Driving (MADD) is a very visible group whose main focus is to educate the public aboutthe harm caused by drunk drivers. A study was recently done that emphasized the problem we all face withdrinking and driving. Five hundred accidents that occurred on a Saturday night were analyzed. Two items notedwere the number of vehicles involved and whether alcohol played a role in the accident. The numbers are shownbelow: Number of Vehicles InvolvedDid alcohol play a role? 1 2 3Yes 60 110 30 200No 40 215 45 300100 325 75What proportion of accidents involved alcohol or a single vehicle?Place your answer, rounded to 2 decimal places, in the blank. For example, 0.23 is a legitimate entry.Question 17 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.Mothers Against Drunk Driving (MADD) is a very visible group whose main focus is to educate the public aboutthe harm caused by drunk drivers. A study was recently done that emphasized the problem we all face withdrinking and driving. Five hundred accidents that occurred on a Saturday night were analyzed. Two items notedwere the number of vehicles involved and whether alcohol played a role in the accident. The numbers are shownbelow: Number of Vehicles InvolvedDid alcohol play a role? 1 2 3Yes 60 110 30 200No 40 215 45 300100 325 75What proportion of accidents involved alcohol and a single vehicle?Place your answer, rounded to 2 decimal places, in the blank. For example, 0.23 is a legitimate entry.Part 8 of 9 -Question 18 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.A popular retail store knows that the purchase amounts by its customers is a random variablethat follows a normal distribution with a mean of $30 and a standard deviation of $9.What is the probability that a randomly selected customer will spend $30 or more at this store?Place your answer, rounded to 4 decimal places, in the blank. For example, 0.3456 would be alegitimate entry.Question 19 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.Suppose that the average weekly earnings for employees in general automotive repair shops is$450, and that the standard deviation for the weekly earnings for such employees is $50. Asample of 100 such employees is selected at random.Find the probability that the mean of the sample is greater than $460. Place your answer,rounded to 4 decimal places, in the blank. For example, 0.2345 would be a legitimateanswer.Question 20 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.A set of final exam scores in an organic chemistry course was found to be normally distributed,with a mean of 73 and a standard deviation of 8.What is the probability of getting a score of 68 or less on this exam? Place your answer,rounded to 4 decimal places in the blank. For example, 0.3456 would be a legitimateentry.Question 21 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.The length of time to complete a door assembly on an automobile factory assembly line isnormally distributed with mean 6.7 minutes and standard deviation 2.2 minutes. For a door selected at random, what is the probability the assembly line time will be between 5 and 10minutes? Place your answer, rounded to 4 decimal places, in the blank. For example, 0.1776would be a legitimate answer.Question 22 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.Scores on a mathematics examination appear to follow a normal distribution with mean of 65and standard deviation of 15. The instructor wishes to give a grade of “C” to students scoringbetween the 60th and 70th percentiles on the exam.What score represents the 60th percentile score on the mathematics exam? Place your answer inthe blank, rounded to a whole number. For example, 62 would be a legitimate entry.Question 23 of 25 1.0 PointsAccepted characters: numbers, decimal point markers (period or comma), sign indicators (-),spaces (e.g., as thousands separator, 5 000), “E” or “e” (used in scientific notation). NOTE: Forscientific notation, a period MUST be used as the decimal point marker.Complex numbers should be in the form (a + bi) where “a” and “b” need to have explicitlystated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.The manufacturer of a new compact car claims the miles per gallon (mpg) for the gasolineconsumption is mound shaped and symmetric with a mean of 25.9 mpg and a standard deviationof 9.5 mpg. If 30 such cars are tested, what is the probability the average mpg achieved by these30 cars will be greater than 28? Place your answer, rounded to 4 decimal places, in theblank.Part 9 of 9 -Question 24 of 25 1.0 PointsUsing the standard normal curve, the Z- score representing the 85th percentile is 0.67TrueFalseReset SelectionQuestion 25 of 25 1.0 PointsUsing the standard normal curve, the Z- score representing the 10th percentile is 1.28.TrueFalse