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A sociologist wants to know the average number of times US families eat their evening meal at home together each week. Data was collected from 50 random families. The sample mean is 3.8 meals per week with a sample standard deviation of 2.5. Construct a 95% confidence interval to estimate the population mean. Then, state this interval below within an interpretive sentence tied to the given context. |
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| Redo #19, only this time assume the value $2.5 is the population standard deviation. Then, state this interval below within an interpretive sentence tied to the given context. | ||||||||||||

A sociologist wants to know the average number of times US families eat their evening meal...
The mean cost of a meal for two in a mid-range restaurant in Tokyo is $40 (Numbeo.com website). How do prices for comparable meals in Hong Kong compare? The table below contains statistics calculated for a sample of 42 recent meals for two in Hong Kong mid-range restaurants. What is the 95% confidence interval estimate of the population mean? How do prices for meals for two in mid-range restaurants in Hong Kong compare to prices for comparable meals in Tokyo...
A sociologist is studying the number of years of education of students whose mothers have bachelor's degrees or higher. The data is normally distributed with a population mean of 14.5 years and a population standard deviation of 2.5 years. If a sample of 55 students is selected at random from the population, select the mean and standard deviation of the sampling distribution below. Select all that apply a. o-×=0.05 years b. o-×= 2.5 years c. o-×= 0.34 years d. u-×=...
A market researcher for a consumer electronics company wants to study the television viewing habits of residents of a particular area. A random sample of 40 respondents is selected, and each respondent is instructed to keep a detailed record of all television viewing in a particular week. The results are as follows: • Viewing time per week: Xbar = 15.3 hours, S = 3.8 hours. • 27 respondents watch the evening news on at least three weeknights. Construct a 95%...
2. In estimating the mean number of television viewing hours per family per week, a random sample of 400 families yields a mean of 32.6 hours and a standard deviation of 9.9 hours (a) Find a 95% confidence interval for the average number of viewing hours per family per week in the population. Interpret. (b) Find a 99% confidence interval for the average number of viewing hours per family per week in the population. Interpret. (c) Suppose instead only 25...
The American Restaurant Association collected information on the number of meals eaten outside the home per week by young married couples. A survey of 60 couples showed the sample mean number of meals eaten outside the home was 2.76 meals per week, with a standard deviation of 0.75 meal per week. Construct a 99% confidence interval for the population mean. Explain which words in the problem indicate a z-distribution or a t-distribution (choose one). Show how to calculate the confidence...
Suppose the math department chair at a large state university wants to estimate the average overall rating, out of five points, that students taking Introductory Statistics gave their lecturers on their end-of-term evaluations. She selects a random sample of 36 evaluations and records the summary statistics shown. Sample size Sample mean Sample standard deviation Population standard deviation Standard deviation of ?¯ Confidence level ? ?⎯⎯⎯ ? ? ??⎯⎯⎯⎯ ? 36 3.8711 1.0755 1.0222 0.1704 95% The department chair determines the...
Suppose the math department chair at a large state university wants to estimate the average overall rating, out of five points, that students taking Introductory Statistics gave their lecturers on their end-of-term evaluations. She selects a random sample of 32 evaluations and records the summary statistics shown. Sample size Sample mean Sample standard deviation Population standard deviation Standard error Confidence level ? ?⎯⎯⎯ ? ? ??⎯⎯⎯⎯ ? 32 3.9102 1.0809 1.0213 0.1805 95% The department chair determines the standard error...
I have done what I can now stuck
15. Researchers are interested in the average height of 11-year old boys. Fifteen randomly selected boys were surveyed and the data is shown to the right heights of 11-year old boys (inches) (a) Determine the mean and standard deviation of this sample data. 56.8 mean 3.78 standard deviation 58 61 55 56.8 3.783422487 (b) Determine the margin of error amount in using this sample result to estimate the average height based upon...
A researcher wants to determine a 99% confidence interval for the mean number of hours that adults spend per week doing community service. How large a sample should the researcher select so that the estimate is within 1.4 hours of the population mean? Assume that the standard deviation for time spent per week doing community service by all adults is 3 hours.
This is all the information that was given in this question. A sociologist claims that children ages 12–14 spent less time sleeping in 1981 than children ages 12–14 do today. A study was conducted in 1981 to find the time that children ages 12–14 spent sleeping on weekdays, with the accompanying results. Assume the population standard deviation is 0.5 hour. Recently a similar study wasconducted, with the accompanying results. Assume the population standard deviation is 0.4 hour. At α equals=0.01,...