AI Tutor
Back to 7.2 The Central Limit Theorem for Sums (Optional)

7.2 Exercise 38

Avg difficulty 2.5

Suppose that the duration of a particular type of criminal trial is known to have a mean of 21 days and a standard deviation of seven days. We randomly sample nine trials.

  1. In words, ΣX = ______________.
  2. ΣX ~ _____(_____, _____)
  3. Find the probability that the total length of the nine trials is at least 225 days.
  4. Ninety percent of the total of nine of these types of trials will last at least how long?

OpenStax Statistics, 7.2 The Central Limit Theorem for Sums (Optional), exercise 38

AI Tutor

Adapted from Statistics © 2022 Rice University. Licensed under CC BY 4.0. Source: Statistics. Imported at revision 7dea80a.