Final answer:
The z-score is calculated using the formula Z = (X - μ) / σ. For an x value of 28.5, with a mean of 27 and a standard deviation of 6.2, the z-score is 0.24 after rounding to two decimal places.
Step-by-step explanation:
To calculate the z-score for an x value of 28.5, with a sample mean of 27 and a sample standard deviation of 6.2, we can use the z-score formula:
Z = (X - μ) / σ
where:
- Z is the z-score
- X is the value for which we want to find the z-score
- μ (mu) is the mean of the data set
- σ (sigma) is the standard deviation of the data set
Substituting the given values, we get:
Z = (28.5 - 27) / 6.2 = 1.5 / 6.2 = 0.241935 (rounded to six decimal places)
Therefore, the z-score, rounded to two decimal places, is 0.24.