Question

systolic blood pressure readings for a population of adults are normally distributed with a mean of 125 and a standard deviation of 20. (a reading above 140 is considered to be high blood pressure.) begin by converting the given blood pressure reading into a z - score. then use the accompanying table of z - scores and percentiles to find the percentage of people with blood pressure readings above 113. click the icon to view the table of z - scores and percentiles. the z - score is . (type an integer or a decimal.)

Explanation:

Step1: Recall z - score formula

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

Step2: Identify values

We are given that $\mu = 125$, $\sigma=20$, and $x = 113$.

Step3: Calculate z - score

Substitute the values into the formula: $z=\frac{113 - 125}{20}=\frac{- 12}{20}=-0.6$.

Answer:

-0.6