Question

One significant consequence of the COVID-19 situation is that many meetings that formerly were held face-to-face are now held virtually using something like Zoom or Skype. Suppose the first population is all face-to-face meetings held in March 2020, the second population is all Zoom meetings held in March 2020, and the parameter of interest is μ₁ – μ₂ = the difference in the mean length of all face-to-face meetings and the mean length of all Zoom meetings. The meeting lengths are measured in minutes. For both face-to-face meetings and Zoom meetings the distributions of meeting times are skewed heavily to the right due to some meetings that are very long. A simple random sample of 83 face-to-face meetings held in March 2020 was selected, and the mean length of this sample of 83 meetings was 46 minutes with a standard deviation of 13.6 minutes. An independent simple random sample of 81 Zoom meetings held in March 2020 was selected, and the mean length of this sample of 81 meetings was 51 minutes with a standard deviation of 11.6 minutes. If appropriate, use this information to calculate and interpret a 90% confidence interval for the difference in the mean length of all face-to-face meetings and the mean length of all Zoom meetings.

Answer 1