Question

The systolic blood pressure of adults in the USA is nearly normally distributed with a mean of 122 and standard deviation of 22 . Someone qualifies as having Stage 2 high blood pressure if their systolic blood pressure is 160 or higher. a. Around what percentage of adults in the USA have stage 2 high blood pressure

Answer 1

Answer: 4.27% of adults in the USA have stage 2 high blood pressure.

Explanation:

Let x be a random variable that denotes a person with high blood pressure .

Given: Average blood pressure:
`\mu=122`

Standard deviation:
`\sigma=22`

Someone qualifies as having Stage 2 high blood pressure if their systolic blood pressure is 160 or higher.

The probability that an adult in the USA have stage 2 high blood pressure:

`P(x\geq160)=P((x-\mu)/(\sigma)}\geq(160-122)/(22))\\\\=P(z\geq1.72)\ \ \ [z=(x-\mu)/(\sigma)]\\\\=1-P(z<1.72)\\\\=1-0.9573\ \ [By\ p-value\ table]\\\\=0.0427=4.27\%`

Hence, 4.27% of adults in the USA have stage 2 high blood pressure.