Can you provide extra explanation on these?

Question 1. Based upon extensive data from a national high school educational testingprogram, the mean score of national test scores for mathematics was found to be 611 and the standard deviation of national test scores for mathematics was found to be 112 points. What is the probability that a random sample of 196 students will have a mean score of more than 620? Less than 591? Question content area bottom Part 1 The probability that a random sample of 196 students will have a mean score of more than 620 is enter your response here. (Round to four decimal places asneeded.)

Question 2.

In determining automobile mileageratings, it was found that the mpg in the city for a certain model is normallydistributed, with a mean of 39 mpg and a standard deviation of 1.7 mpg. Suppose that the car manufacturer samples seven cars from its assembly line and tests them for mileage ratings. a. What is the distribution of the mean mpg for thesample? b. What is the probability that the mean mpg of the sample will be greater than 41 mpg? c. What is the probability that the mean mpg of the sample will be less than 38.5 mpg? Question content area bottom Part 1 a. What is the distribution of the mean mpg for thesample? Select the correct choice below and fill in the answer boxes to complete your choice. (Type integers or decimals rounded to two decimal places asneeded.)A.The sampling distribution of the mean follows a triangular distribution with the sample mean enter your response here mpg and the standard deviation of the sample mean enter your response here mpg.B.The sampling distribution of the mean follows a normal distribution with the sample mean enter your response here mpg and the standard deviation of the sample mean enter your response here mpg.C.The sampling distribution of the mean follows an exponential distribution with the sample mean enter your response here mpg and the standard deviation of the sample mean enter your response here mpg.D.The sampling distribution of the mean follows a uniform distribution with the sample mean enter your response here mpg and the standard deviation of the sample mean enter your response here mpg.

Question 3

From a sample of 21 graduatestudents, the mean number of months of work experience prior to entering an MBA program was 36.82. The national standard deviation is known to be 18 months. What is a 99% confidence interval for the populationmean? Question content area bottom Part 1 A 99% confidence interval for the population mean is enter your response here,enter your response here. (Use ascending order. Round to two decimal places asneeded.)

Question 4

A survey of 220 young professionals found that two-thirds of them use their cell phones primarily fore-mail. Can you conclude statistically that the population proportion who use cell phones primarily fore-mail is less than 0.72? Use a95% confidence interval. Question content area bottom Part 1 The95% confidence interval is enter your response here,enter your response here. As 0.72 is above the upper limit within the limits below the lower limit of the confidenceinterval, we cannot can conclude that the population proportion is less than 0.72. (Use ascending order. Round to four decimal places asneeded.)

Question 4.

The accompanying table gives the results of a survey of 19 patients at ahospital, with95% confidence intervals. Construct a stockchart-based visualization of these confidence intervals. What conclusions can you draw from thechart? Satisfaction with Quality of Care from Nurses Satisfaction with Quality of Care from Specialists Satisfaction with Quality of Care from Practitioners Sample Proportion 1619 1419 1819 Upper 1.012 0.785 0.994 Lower 0.676 0.733

Question 5

Tradeassociations, such as a dairyassociation, frequently conduct surveys to identify characteristics of their membership. If this organization conducted a survey to estimate the annual per capita consumption of milk and wanted to be

99%

confident that the estimate was no more than

0.74

gallon away from the actualaverage, what sample size isneeded? Past data have indicated that the standard deviation of consumption is approximately

9

gallons.

Question content area bottom

Part 1

The sample size required is

enter your response here.

Question 6.

A survey of

30

college freshmen found that they average

6.15

hours of sleep each night. A

99%

confidence interval had a margin of error of

0.522.

a. What are the lower and upper limits of the confidenceinterval?

b. What was the standarddeviation, assuming that the population standard deviation isknown?

Question content area bottom

Part 1

a. The lower limit of the confidence interval is

enter your response here

and the upper limit of the confidence interval is

enter your response here.

Question 7

A sample of

36

individuals at a shopping mall found that the mean number of visits to a restaurant per week was

2.96

with a standard deviation of

1.56.

Find a

90%

confidence interval for the mean number of restaurant visits.

Question content area bottom

Part 1

A

90%

confidence interval for the mean number of restaurant visits is

enter your response here,enter your response here.