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OpenStax, Introductory Statistics 2e §7.3 Using the Central Limit Theorem · Exercise 25 · Statistics · Sampling distributions

Using the Central Limit Theorem · Exercise 25

The attention span of a two-year-old is exponentially distributed with a mean of about eight minutes. Suppose we randomly survey 60 two-year-olds.

(a) In words, Χ = _______
(b) Χ ~ _____(_____,_____)
(c) In words, = ____________
(d) ~ _____(_____,_____)
(e) Before doing any calculations, which do you think will be higher? Explain why.
(a) The probability that an individual attention span is less than ten minutes.
(b) The probability that the average attention span for the 60 children is less than ten minutes?
(f) Calculate the probabilities in part e.
(g) Explain why the distribution for is not exponential.

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OpenStax, Introductory Statistics 2e · §7.3 Using the Central Limit Theorem · Exercise 25

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