Question

systolic blood pressure readings for a population of adults are normally distributed with a mean of 119 and a standard deviation of 16 (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 below 143.
click the icon to view the table of z - scores and percentiles.
the z - score is 1.5.
(type an integer or a decimal.)
the percentage of people with blood pressure readings below 143 is
(round to two decimal places as needed.)

Explanation:

Step1: Recall Z - table usage

To find the percentage of people with blood pressure below 143, we use the z - score of 1.5. We refer to the standard normal distribution (Z - table) which gives the cumulative probability \( P(Z < z) \) for a given z - score.

Step2: Look up z - score in Z - table

For a z - score of 1.5, we look at the Z - table. The row for 1.5 and the column for 0.00 (since 1.5 = 1.50) gives the value. From the Z - table, \( P(Z < 1.5)=0.933193 \)

Step3: Convert to percentage

To convert the probability to a percentage, we multiply by 100. So, \( 0.933193\times100 = 93.3193\% \)

Step4: Round to two decimal places

Rounding 93.3193% to two decimal places, we get 93.32%.

Answer:

93.32