The mean systolic blood pressure for a sample of 500 individuals is 110 with a standard deviation of 16. A patient's systolic blood pressure is measured at 84. What is the z-score for this measurement?
A) -26
B) 1.62
C) 26.00
D) -1.62

Question

Quizplus · Accepted Answer

The z-score formula is:
z = (x - μ) / σ

where:
x = the individual measurement
μ = the population mean
σ = the population standard deviation

Plugging in the given values, we get:
z = (84 - 110) / 16
z = -1.625

Rounding to two decimal places, the z-score for this measurement is -1.62.

Therefore, the best choice is D: -1.62.

The Mean Systolic Blood Pressure for a Sample of 500