If commuting times are normally distributed with mean 31.3 minutes and standard deviation 13.2 minutes, what is the z-score (the number of standard deviations away from the mean) of a 28.7 minute commute

what measure of variability is to be computed with a median

Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 9 million dollars and a standard deviation of 1.4 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 10% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place.

Suppose the distribution of typing speeds in words per minute for experienced typists can be approximated by a normal curve with a mean of 60 wpm and a standard deviation of 15 wpm. To be considered for a position an applicant needs to have a typing speed of at least 70 wpm. If 62 experienced typists apply for the job, how many of these would be considered based on their typing speed?

In a set of 48 months of data for medical the mean is 15 days and standard deviation of 4.2 how many months fewer than 19.2 days per month reported medical leave ( one standard deviation above the mean?

A survey among freshmen at a certain university revealed that the number of hours spent studying the week before final exams was normally distributed with mean 25 and standard deviation 9.  Between what two values are the middle 80% of the hours spent studying?

Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 8 million dollars and a standard deviation of 1.3 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 10% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place. 00 0 million dollars X S ? Check acer Q tab esc ! 1 9. a @ 2 W →> S #m 3 X e C d $ LAS 4 C r % 5 f t > < 6 g y & JX b 7 h C n K1300

A sociologist found that in a sample of 45 retired men, the average number of jobs they had during theirlifetimes was 7.2. The population standard deviation is 2.3(a) Find the best point estimate of the mean.The best point estimate of the mean is

A study of commuting times reports the travel times to work of a random sample of 1068 employed adults in Chicago. The mean is x = 54.0 minutes and the standard deviation is s = 60.9 minutes. What is the standard error of the mean?

If IQ scores are normally distributed with a mean of 100 and a standard deviation of 15, what is P85?