Answer:
2.50 standard deviations above the mean
Step-by-step explanation:
The z-score measures how many a measure is above or below the mean. If the score is positive it is above the mean. If it is negative, it is below. The zscore is given by
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
In which [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.
In this problem, we have that:
[tex]\mu = 39, \sigma = 10[/tex]
Last year there were 64 inches of snow. How many standard deviations from the mean is that?
This is Z when X = 64. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{64 - 39}{10}[/tex]
[tex]Z = 2.5[/tex]
So the correct answer is:
2.50 standard deviations above the mean
