A set of data items is normally distributed with a mean of 60 and a standard deviation of 12. Convert the data item 48 to a z-score.

so whats the answer

To convert a data item to a z-score, you need to use the formula:

z = (x - μ) / σ

where:
z is the z-score,
x is the data item,
μ is the mean, and
σ is the standard deviation.

In this case, you have the following values:
x = 48 (data item)
μ = 60 (mean)
σ = 12 (standard deviation)

Now, plug these values into the formula:

z = (48 - 60) / 12

Simplifying the equation:
z = -12 / 12
z = -1

So, the z-score for the data item 48 is -1.

as before, 48 = µ - 1σ