The systolic blood pressure given in millimeters of males ha

The systolic blood pressure (given in millimeters) of males has an approximately normal distribution with mean ? = 125 and standard deviation ? = 14. Systolic blood pressure for males follows a normal distribution. a. Calculate the z-scores for the male systolic blood pressures 100 and 150 millimeters. b. If a male friend of yours said he thought his systolic blood pressure was 2.5 standard deviations below the mean, but that he believed his blood pressure was between 100 and 150 millimeters, what would you say to him?

Solution

A. Calculate z-scores for 100 and 150

(100-125)/14=-1.79

(150-125)/14=1.79

B. Calculate blood pressure for 2.5 SD below mean

2.5(14)=35

His blood pressure=125-35=90

So he is incorrect, 2.5 SD below the mean equals a blood pressure of 90mm.