Calculate the standard score (z-score) of the given sample mean. Round your answer to two decimal places.
μ=31 and σ=9; n=64; x¯=30

The standard score (z-score) of the given sample mean is equal to 7.11What is a standard score?A standard score is also referred to as a z-value or z-score and it can be defined as a measure of the distance between a raw score and the mean, when standard deviation units are used.Mathematically, the standard score of a given sample mean can be calculated by using this formula:[tex]Z=\frac{\bar{x}\;-\;\mu}{ \frac{\delta}{n} }[/tex]Where:Where:x represents the sample score.u represents the mean point.z represents the standard score.σ represents the standard deviation.n represents the number of samples.Substituting the given parameters into the formula, we have;Standard score, z = (30 - 31)/(9/64)Standard score, z = -1/0.140625Standard score, z = 7.11Read more on z-scores here: https://brainly.com/question/26714379#SPJ1