OpenStax, Statistics §7.2 The Central Limit Theorem for Sums (Optional) · Exercise 25 · Statistics · Sampling distributions
The Central Limit Theorem for Sums (Optional) · Exercise 25
A market researcher analyzes how many electronics devices customers buy in a single purchase. The distribution has a mean of three with a standard deviation of 0.7. She samples 400 customers.
What is the z-score for Σx = 840?
OpenStax, Statistics · §7.2 The Central Limit Theorem for Sums (Optional) · Exercise 25
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