Final answer:
The z-score is calculated by subtracting the mean from the value and then dividing by the standard deviation. In this case, the z-score for x = 30.4 with a mean of 33 and a standard deviation of 7.3 is -0.36.
Step-by-step explanation:
To calculate the z-score for the given value x = 30.4 with a sample mean (μ) of 33 and a sample standard deviation (s) of 7.3, you use the formula:
z = (x - μ) / s
Plugging in the numbers:
z = (30.4 - 33) / 7.3
z = -2.6 / 7.3
z = -0.3562...
Rounded to two decimal places, the z-score is -0.36.
The z-score tells you how many standard deviations an element x is from the mean. In this case, a z-score of -0.36 indicates that 30.4 is less than one standard deviation below the mean.