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OpenStax, Introductory Statistics 2e §7.2 The Central Limit Theorem for Sums · Exercise 32 · Statistics · Sampling distributions

The Central Limit Theorem for Sums · Exercise 32

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.

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

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OpenStax, Introductory Statistics 2e · §7.2 The Central Limit Theorem for Sums · Exercise 32

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