A standard race is the 100 m sprint, with Usain Bolt holding the record at 9.58 seconds. Suppose a researcher asks 105 men to run 100 m and finds a mean of 24 and a sample standard deviation of 5. What is a 95% confidence interval for the average running time and would you expect Usain's time to be in the interval?   a. The interval 23.043 to 24.956 and Usain's time is a rare event - a freak occurrence that happened by chance b. The interval is 23.043 to 24.956 but Usain's time is unrelated to this confídence interval c. The interval is 14.2 to 33.8 and Usain's time is a non-random draw since professional runners like Ussain are chosen for their low times. d.  The interval is 23.043 to 24.956 and Usain's time is a non-random draw since professional runners like Usair are chosen for their low times

The Aluminum Association reports that the average American uses 56.8 pounds of aluminum in a year. A random sample of 49 households is monitored for one year to determine aluminum usage. If the population standard deviation of annual usage is 12.1 pounds, what is the probability that the sample mean will be each of the following? Appendix A Statistical Tables a. More than 58 poundsb. More than 56 poundsc. Between 55 and 57 poundsd. Less than 54 poundse. Less than 48 pounds(Round the values of z to 2 decimal places. Round your answers to 4 decimal places.)a. enter the probability that the sample mean will be more than 58 poundsb. enter the probability that the sample mean will be more than 56 poundsc. enter the probability that the sample mean will be between 55 and 57 poundsd. enter the probability that the sample mean will be less than 54 poundse. enter the probability that the sample mean will be less than 48 pounds

A leading magazine (like Barron's) reported at one time that the average number of weeks an individual is unemployed is 35.2 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 35.2 weeks and that the population standard deviation is 5.6 weeks. Suppose you would like to select a random sample of 29 unemployed individuals for a follow-up study. Find the probability that a single randomly selected value is between 33.1 and 33.8. P(33.1 < X < 33.8) = 0.0475 29 is Find the probability that a sample of size n randomly selected with a mean between 33.1 and 33.8. Р(3.1 < М < 33.8) - Enter your answers as numbers accurate to 4 decimal places.

Salaries of 25 college graduates who took a statistics course in college have a​ mean of $79,350 and a standard​ deviation of $1,280​. Construct a 98​% confidence interval for estimating the population standard deviation. Enter the upper bound of the confidence interval. (Round your answer to nearest whole dollar.)

In a local university, 80% of the students live in the dormitories. A random sample of 64 students is selected for a particular study. The standard deviation of p-bar is   a. 64   b. 0.05   c. 1.6   d. 0.16   e. 0.5