Answer:
1.221
Step-by-step explanation:
We have been given that an observation was drawn from a normally distributed population with mean 2.397 and standard deviation 0.612. We are asked to find the z-score of an observed value of 3.144.
We will use z-score formula to solve our given problem.
[tex]z=\frac{x-\mu}{\sigma}[/tex], where,
z = Z-score,
x = Sample score,
[tex]\mu[/tex] = Mean,
[tex]\sigma[/tex] = Standard deviation.
Upon substituting our given values in z-score formula, we will get:
[tex]z=\frac{3.144-2.397}{0.612}[/tex]
[tex]z=\frac{0.747}{0.612}[/tex]
[tex]z=1.2205882352941176[/tex]
Round to three decimal places, we will get:
[tex]z\approx 1.221[/tex]
Therefore, our required z-score would be 1.221.