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2022-10-08
Answered

What is the z-score of sample X, if $n=36,\text{}\mu =12.3,\text{}\text{St.Dev}=47,\text{}{\mu}_{X}=18.5$?

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Jase Powell

Answered 2022-10-09
Author has **11** answers

Given

$n=36\phantom{\rule{0ex}{0ex}}\mu =12.3\phantom{\rule{0ex}{0ex}}\text{St.Dev}=47\phantom{\rule{0ex}{0ex}}{\mu}_{X}=18.5$

Find the Standard Error

$SE=\frac{\sigma}{\sqrt{n}}=\frac{47}{\sqrt{36}}=7.8$

Find the z-score

$z=\frac{18.5-12.3}{7.8}=0.79$

$n=36\phantom{\rule{0ex}{0ex}}\mu =12.3\phantom{\rule{0ex}{0ex}}\text{St.Dev}=47\phantom{\rule{0ex}{0ex}}{\mu}_{X}=18.5$

Find the Standard Error

$SE=\frac{\sigma}{\sqrt{n}}=\frac{47}{\sqrt{36}}=7.8$

Find the z-score

$z=\frac{18.5-12.3}{7.8}=0.79$

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