Question

1. a dataset has $mu = 70$ and $sigma = 10$. what is the z - score for $x = 90$?

a. 1.5
b. 1
c. 3
d. 2

Explanation:

Step1: Recall z - score formula

The z - score formula is $z=\frac{x-\mu}{\sigma}$, where $x$ is the data - point, $\mu$ is the mean, and $\sigma$ is the standard deviation.

Step2: Substitute given values

We are given that $\mu = 70$, $\sigma=10$, and $x = 90$. Substitute these values into the formula: $z=\frac{90 - 70}{10}$.

Step3: Calculate the z - score

First, calculate the numerator: $90−70 = 20$. Then, divide by the denominator: $\frac{20}{10}=2$.

Answer:

d. 2