According to the IRS study, it takes a mean of 330 minutes for taxpayers to make, copy, and electronically file a 1040 tax form. This distribution of times follows normal distribution and the standard deviation is 80 minutes. A consumer watchdog agency chooses a random sample of 40 taxpayers.
Determine the standard error of the mean in this example?
Compute the likelihood the sample mean is greater than 320 minutes?
Estimate the likelihood the sample mean is between 320 and 350 minutes?
Determine the likelihood the sample mean is greater than 350 minutes?