In order to estimate the mean amount of time computer users spend on the internet each month, how many computer users must be surveyed in order to be 95% confident that your sample mean is within 12 minutes of the population mean? assume that the standard deviation of the population of monthly time spent on the internet is 213 min. what is a major obstacle to getting a good estimate of the population mean? use technology to find the estimated minimum required sample size. the minimum sample size required is 1211 computer users. (round up to the nearest whole number.) what is a major obstacle to getting a good estimate of the population mean?

Christine wong has asked dave and mike to her move into a new apartment on sunday morning. she has asked them both, in case one of them does not show up. from past experience, christine knows that there is a 40% chance that dave will not show up and a 30% chance that mik a. what is the probability that both dave and mike will show up? (round your answer to 2 decimal places.) b. what is the probability that at least one of them will show up? c. what is the probability that neither dave nor mike will show up? (round your answer to 2 decimal places.)e will not show up. dave and mike do not know each other and their decisions can be assumed to be independent.