Question

Part 1

The systolic blood pressure of adults in the USA is nearly normally distributed with a mean of 120 and standard deviation of 23 .

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

Part 2

In the country of United States of Heightlandia, the height measurements of ten-year-old children are approximately normally distributed with a mean of 55.2 inches, and standard deviation of 8.7 inches.

What is the probability that the height of a randomly chosen child is between 44.35 and 45.05 inches? Do not round until you get your final answer, and then round to 3 decimal places.

Part 3

A distribution of values is normal with a mean of 130.7 and a standard deviation of 89.2.

Find the probability that a randomly selected value is greater than 202.1.
P(X > 202.1) =

Part 4

A distribution of values is normal with a mean of 150.1 and a standard deviation of 78.5.

Find the probability that a randomly selected value is between -38.3 and -30.5.
P(-38.3 < X < -30.5) =

Part 5

Company XYZ know that replacement times for the portable MP3 players it produces are normally distributed with a mean of 3.6 years and a standard deviation of 1.1 years.

Find the probability that a randomly selected portable MP3 player will have a replacement time less than 0.5 years?
P(X < 0.5 years) = ________

Enter your answer accurate to 4 decimal places. Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted.

If the company wants to provide a warranty so that only 4.4% of the portable MP3 players will be replaced before the warranty expires, what is the time length of the warranty?
warranty = _______ years

Part 6

The combined SAT scores for the students at a local high school are normally distributed with a mean of 1503 and a standard deviation of 308. The local college includes a minimum score of 1626 in its admission requirements.

What percentage of students from this school earn scores that fail to satisfy the admission requirement?
P(X < 1626) = _______%

Answer 1

​​​​​​​​​pl​​Please post the other questions separately. As per our answering guidelines we are supposed to answer just one question or four sub parts of the same question.