Use technology to solve the following problem: A recent study reported that diastolic blood pressures of adult women in the United States are approximately normally distributed with mean 80.6 and standard deviation 9.9. What proportion of women have blood pressures higher than 85.8?
A) 0.7003
B) 0.3501
C) 0.6499
D) 0.2997

Question

Quizplus · Accepted Answer

To find the proportion of women with blood pressures higher than 85.8, we use the Z-score formula: $Z = \frac{X - \mu}{\sigma}$, where $X$ is the value of interest (85.8), $\mu$ is the mean (80.6), and $\sigma$ is the standard deviation (9.9). Calculating the Z-score gives us $Z = \frac{85.8 - 80.6}{9.9} = 0.5253$. Looking up this Z-score in a standard normal distribution table or using a calculator's normal distribution function, we find that the area to the left of this Z-score is approximately 0.7003, meaning the area to the right (the proportion of women with blood pressures higher than 85.8) is 1 - 0.7003 = 0.2997.

Use Technology to Solve the Following Problem: a Recent Study