9. Consider the variable x = time required for a college student to complete a standardized...
9. Consider the variable x = time required for a college student to complete a standardized exam. Suppose that for the population of students at a particular university, the distribution of x is well approximated by a normal curve with mean 45 min and standard deviation 5 min. Consider random samples of size 25 from the population.
a. Sketch the sampling distribution of the sample mean. You need not get the graph perfectly correct, but should clearly indicate different aspects of the distribution, such as mean, standard deviation.
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9. Consider the variable x = time required for
a college student to complete a standardized...
(2 points) For students in a certain region, scores of students on a standardized test approximately...
(2 points) For students in a certain region, scores of students on a standardized test approximately follow a normal distribution with mean u = 543.4 and standard deviation o = 26.9. In completing the parts below, you should use the normal curve area table that is included in your formula packet. (a) What is the probability that a single randomly selected student from among all those in region who took the exam will have a score of 548 or higher?...
Total sleep time of college students. A recent survey describes the distribution of total sleep time...
Total sleep time of college students. A recent survey describes the distribution of total sleep time among college students as approximately Normal with a mean of 6.78 hours and standard deviation of 1.24 hours.3 Suppose that we select a college student at random and obtain his or her sleep time. This result is a random variable X because, prior to the random sampling, we don't know the sleep time. We do know, however, that in repeated sampling, X will have...
(4) The time required to complete a final exam in a particular college course is normally...
(4) The time required to complete a final exam in a particular college course is normally distributed with a mean of 75 minutes and a standard deviation of 15 minutes. Answer the following questions: (a) (for a randomly selected student) What is the probability of completing the exam in 1 hour or less? (4) (b) What is the probability a randomly selected student will complete the exam in more than 60 minutes but less than 75 minutes? (4b) (c) Assume...
let x be the random variable that represent the lenght of time it takes a student...
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The time needed for college students to complete a certain paper-and-pencil maze follows a normal distribution...
The time needed for college students to complete a certain paper-and-pencil maze follows a normal distribution with a mean of µ = 30 seconds and a standard deviation of σ = 3 seconds. Nine randomly selected college students complete the maze. The sampling distribution of the sample mean X it takes the sampled students to complete the maze is A. normal with mean 30 and standard deviation 3. B. normal with mean 30 and standard deviation 1. C. negatively skewed...
The scores of students on the SAT college entrance examinations at a certain high school had...
The scores of students on the SAT college entrance examinations at a certain high school had a normal distribution with mean μ=557.1 and standard deviation σ=29. (a) What is the probability that a single student randomly chosen from all those taking the test scores 562 or higher? For parts (b) through (d), consider a simple random sample (SRS) of 35 students who took the test. (b) What are the mean and standard deviation of the sample mean score x¯, of...
Suppose student test scores for a nationwide standardized test have an unknown distribution with mean 230...
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The scores of students on the SAT college entrance examinations at a certain high school had...
The scores of students on the SAT college entrance examinations at a certain high school had a normal distribution with mean ?=537μ=537 and standard deviation ?=27.5σ=27.5. (a) What is the probability that a single student randomly chosen from all those taking the test scores 542 or higher? ANSWER: For parts (b) through (d), consider a simple random sample (SRS) of 25 students who took the test. (b) What are the mean and standard deviation of the sample mean score ?¯x¯,...
The annual salary for one particular occupation is normally distributed, with a mean of about $133 comma 000 and a sta...
The annual salary for one particular occupation is normally distributed, with a mean of about $133 comma 000 and a standard deviation of about $15 comma 000. Random samples of 28 are drawn from this population, and the mean of each sample is determined. Find the mean and standard deviation of the sampling distribution of these sample means. Then, sketch a graph of the sampling distribution. The mean is mu Subscript x over bar equals nothing, and the standard deviation...
The scores of students on the SAT college entrance examinations at a certain high school had...
The scores of students on the SAT college entrance examinations at a certain high school had a normal distribution with mean μ=553.3 and standard deviation σ=28.6.Round z-scores to 2 decimal places and give probabilities to 4 decimal places. (a) What is the probability that a single student randomly chosen from all those taking the test scores 558 or higher? ANSWER: For parts (b) through (d), consider a simple random sample (SRS) of 30 students who took the test. (b) What...
(2 points) For students in a certain region, scores of students on a standardized test approximately follow a normal distribution with mean u = 543.4 and standard deviation o = 26.9. In completing the parts below, you should use the normal curve area table that is included in your formula packet. (a) What is the probability that a single randomly selected student from among all those in region who took the exam will have a score of 548 or higher?...
Total sleep time of college students. A recent survey describes the distribution of total sleep time among college students as approximately Normal with a mean of 6.78 hours and standard deviation of 1.24 hours.3 Suppose that we select a college student at random and obtain his or her sleep time. This result is a random variable X because, prior to the random sampling, we don't know the sleep time. We do know, however, that in repeated sampling, X will have...
(4) The time required to complete a final exam in a particular college course is normally distributed with a mean of 75 minutes and a standard deviation of 15 minutes. Answer the following questions: (a) (for a randomly selected student) What is the probability of completing the exam in 1 hour or less? (4) (b) What is the probability a randomly selected student will complete the exam in more than 60 minutes but less than 75 minutes? (4b) (c) Assume...
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