What is the z-score of sample X, if n = 55, mu= 38, St. Dev. =66, and mu_X =43?

Dec 16, 2016

The answer is $z = 0.56$

Explanation:

The z-score for a sample mean is

$z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

$\overline{x} = {\mu}_{x} = 43$

$\mu = 38$

$\sigma = 66$

$n = 55$

$z = \frac{43 - 38}{\frac{66}{\sqrt{55}}}$

$= \frac{5}{8.9} = 0.56$