Question

The systolic blood pressure of adults in the USA is nearly normally distributed with a mean of 117 and standard deviation of 21 .

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? Give your answer rounded to two decimal places.

%





b. If you sampled 2000 people, how many would you expect to have BP> 160? Give your answer to the nearest person. Note: I had a bit of an issue encoding rounded answers, so try rounding both up and down if there's an issue!

people





c. Stage 1 high BP is specified as systolic BP between 140 and 160. What percentage of adults in the US qualify for stage 1?

%



d. Your doctor tells you you are in the 30th percentile for blood pressure among US adults. What is your systolic BP? Round to 2 decimal places.

lbs

Answer 1

a) Let X denotes the systolic blood pressure of a randomly selected adult in the USA.

X ~ Normal(117, 21²)

The percentage of adults in the USA have stage 2 high blood pressure = 100*P(X>=160) = 100*0.0203 = 2.03%

b)

c)

The percentage of adults in the US qualify for stage 1 = 100*0.116407 = 11.64%

d)