OpenStax, Statistics §7.2 The Central Limit Theorem for Sums (Optional) · Try It 2 · Statistics · Sampling distributions
The Central Limit Theorem for Sums (Optional) · Try It 2
In a recent study reported Oct.29, 2012, the mean age of tablet users is 35 years. Suppose the standard deviation is 10 years. The sample size is 39.
(a) What are the mean and standard deviation for the sum of the ages of tablet users? What is the distribution?
(b) Find the probability that the sum of the ages is between 1,400 and 1,500 years.
(c) Find the 90^th percentile for the sum of the 39 ages.
OpenStax, Statistics · §7.2 The Central Limit Theorem for Sums (Optional) · Try It 2
Stuck? A gentle nudge
No hints for this one.
Your working
Check your full solution
Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.