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.
a
-1
b
-12
c
12
d
1
search :
David Lane normal distribution
https://davidmlane.com/hyperstat/z_table.html
To convert a data item to a z-score, we use the formula:
z = (x - μ) / σ
Where:
- z is the z-score
- x is the data item
- μ is the population mean
- σ is the population standard deviation
In this case:
- x = 48
- μ = 60
- σ = 12
Plugging in the values into the formula, we get:
z = (48 - 60) / 12
Calculating this, we get:
z = -1
Therefore, the z-score for the data item 48 is -1.
So, the correct answer is option a.