According to eMarketer, adults in the U.S. average 210 minutes per day on mobile devices. Assume that minutes per day on mobile devices follow a normal distribution with a mean of 210 minutes and standard deviation of 60 minutes. (a) What percentage of adults spend more than 3 hours (180 minutes) on their mobile devices per day? (b) What percentage of adults spend between 120 and 300, minutes on their mobile devices per day?
According to eMarketer, adults in the U.S. average 210 minutes per day on mobile devices. Assume...
Question 5 An carlier study claimed that U.S adults spent an average of 114 minutes per day with their family. A recently raken sample of 25 adults from a city show'eod that they spend an average of 109 minutes per day with their family, Ihe population deviation is I1 minutes. Assume that the times spent by adults with their families have an approximate normal distribution Using a 1% significance level test whether the mean time spent currently by all adults...
) According to a certain survey, adults spend 2.252.25 hours per day watching television on a weekday. Assume that the standard deviation for "time spent watching television on a weekday" is 1.931.93 hours. If a random sample of 6060 adults is obtained, describe the sampling distribution of x overbarx, the mean amount of time spent watching television on a weekday. x overbarx is approximately normal with mu Subscript x overbarμxequals= 2.25 and sigma Subscript x overbarσxequals=0.2491620.249162 . (Round to six...
The following data show the number of hours per day 12 adults spent in front of screens watchin 4.3 4.5 7.4 1.3 5.7 4.6 3.4 7.9 2.2 5.1 1.7 8.3 a. Construct a 99% confidence interval to estimate the average number of hours per day adults s The 99% confidence interval to estimate the average number of hours per day adults spend (Round to two decimal places as needed.) b. What assumptions need to be made about this population? O...
Question 7 5 pts According to research, the amount of sleep per night for U.S adults follows a normal distribution with a mean p = 7.25 hours and standard deviation o - 1.25 hours. Determine the proportion of people who get between 5.0 and 9.0 hours of sleep per night. Use the provided Standard Normal Table (Z table), and provide the proportion as a decimal rounded to four decimal places.
7. Digital Viewing Times According to eMarketer, the average time spent per day with digital media in 2010 was 3 hours and 14 minutes. For last year, a random sample of 20 Americans adults spent the following number of hours per day with digital media. 1.4 5.0 5.8 4.1 5.6 2.1 6.5 2.3 8.0 9.5 7.3 5.9 9.4 4.3 2.9 2.8 5.1 4.5 4.1 6.6 Find and interpret a 90% confidence interval for the mean time spent with digital media...
According to a certain survey, adults spend 2.35 hours per day watching television on a weekday. Assume that the standard deviation for "time spent watching television on a weekday" is 1.93 hours. If a random sample of 50 adults is obtained, describe the sampling distribution of x overbar, the mean amount of time spent watching television on a weekday. One consequence of the popularity of the Internet is that it is thought to reduce television watching. Suppose that a random...
According to a recent study, the population of U.S. citizens spend, on average, 30 hours per week watching television, with a standard deviation of 5.25 hours. If a random sample of n = 36 consumers is drawn from this population, what is the probability that the sample mean will be no more than 29.3 hours per week?
The average employee in the U.S.A. spends μ = 23 minutes commuting to work each day. Assume that the distribution of commute times is normal with a standard deviation of σ = 8 minutes. (a) What proportion of U.S. employees spend less than 15 minutes a day commuting? (b) What is the probability of randomly selecting an employee who spends more than 35 minutes commuting each day?
The following data show the number of hours per day 12 adults spent in front of screens watching television-related content. Complete parts a and b below 51 16 5.3 7.8 21 6.90 8.8 29 13 52 hours to hours a. Construct a 90% confidence interval to estimate the average number of hours per day adults spend in front of screens watching television-related content The 90% confidence interval to estimate the average number of hours per day adults spend in front...
The following data show the number of hours per day 12 adults spent in front of screens watching television-related content. Complete parts a and below. 1.3 5.7 4.6 3.4 4.3 5.1 7.9 7.40 8.3 1.7 2.2 a. Construct a 99% confidence interval to estimate the average number of hours per day adults spend in front of screens watching television-related content. The 90% confidence interval to estimate the average number of hours per day adults spend in front of screens watching...