# What is the z-score of sample X, if n = 36, mu= 5, St. Dev. =9, and mu_X =6?

$z = \frac{2}{3} \cong 0.6666666$

#### Explanation:

The given data are $n = 36$ and $\mu = 5$ and $\sigma = 9$ and ${\mu}_{x} = 6$

The formula

$z = \frac{{\mu}_{x} - \mu}{\left(\frac{\sigma}{\sqrt{n}}\right)}$

$z = \frac{6 - 5}{\left(\frac{9}{\sqrt{36}}\right)}$

$z = \frac{1}{\left(\frac{9}{6}\right)}$

$z = \frac{2}{3}$

God bless....I hope the explanation is useful.