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Chapter 7: Q.32 (page 429)

What is the z-score for Σx = 1,186?

Short Answer

Expert verified

The Z- score is approximately-1

Step by step solution

01

Given Information

According to the Given details, the sample size of customers is 1186 with a mean 3 and the standard deviation is 0.7.

02

Explanation

The sum of values is 840, so theZ-score is given as:

∑X=(n)μX+(z)(n)σX

1186=400×3+(z)×400×0.7

-14=14.0(z)

z=-1

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