The lengths of pregnancies are normally distributed with a mean of 280 days and a standard deviation of 16 days.(a) Find the probability that an individual woman has a pregnancy shorter than 271 days.(b) If 25 women are randomly selected, find the probability that they have a mean pregnancy shorter than 271 days.(c) There should be a difference in your method for the previous two questions. Explain what you did differently for each problem and explain WHY your answers are different.(d) Find the probability that an individual woman has a pregnancy longer than 300 days.(e) Find the probability that an individual woman has a pregnancy between 280 and 300 days.(f) What is the cutoff number of days for a pregnancy for the top 15% of women?(g) What is the cutoff number of days for a pregnancy for the bottom 20% of women?

As per our guidelines, we are allowed to answer first thee sub-parts only. Thanks μ = 280σ=16 a)…

Answered: The lengths of pregnancies are normally…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1549 and the standard deviation was 318. The test scores of four students selected at random are 1960,1270, 2250, and 1450. Find the z-scores that correspond to each value and determine whether any of the values are unusual.
Mario's weekly poker winnings have a mean of $353 and a standard deviation of $67. Last week he won $185. How many standard deviations from the mean is that?
Suppose the scores on your last Algebra 2 test were normally distributed, with a mean of 81% and a standard deviation of 3%. To show you how you compared to your classmates, the teacher did not record your grades as per- centages, instead, she wrote them as z-scores. You look at your paper and see "2.66" written at the top. What was your score as a percentage? Explain how you determined your answer.
A successful basketball player has a height of 6 feet 11 inches, or 211 cm. Based on statistics from a data set, his height converts to the z score of 5.17. How many standard deviations is his height above the mean?
A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1471 and the standard deviation was 317. The test scores of four students selected at random are 1900,1200,2200,and 1370. Find the z-scores that correspond to each value and determine whether any of the values are unusual.
To celebrate the end of final exams you and friends head to a favorite downtown restaurant. You find a street parking spot with a maximum of two hours. If you stay longer than two hours, you risk having your car towed away. No one has a watch or cellphone but you remember that the average time you spent at the same restaurant over your previous 16 visits is 1.5 hours, and you estimate the sample standard deviation to be about 20 minutes. You also need to factor in that it takes 8 minutes to walk to the restaurant and 8 minutes to walk back to your car (you are very certain about these two durations). (a) One of your friends is really worried that you won’t get back to the car in time and so the car might be towed away! Does your friend have good reason to be worried? Test at a 5% significance level whether the mean total time will be less than two hours. (b) You decide to leave the car parked at the street spot but it gets towed. What type of error have you committed?
You determine that the standard deviation for a sample of test scores is 0. This tells you that 1 all the test scores must be 0. 2 all the test scores must be the same value. 3 there is no straight-line association. 4 the mean test score must also be 0. 5 you made a mistake because the standard deviation can never be 0.
Deandre is in his first semester at a certain university and is taking a calculus course with a large enrollment. He just took the first midterm exam and is nervous about his score. Among all of the students in the course, the mean of the exam was 67 with a standard deviation of 3. Deandre scored a 62 on this exam. (a) Find the z-score of Deandre's exam score relative to the exam scores among all the students in the course. Round your answer to two decimal places. z=0 (b) Fill in the blanks to interpret the z-score of Deandre's exam score. Make sure to express your answer in terms of a positive number of standard deviations. Deandre's exam score was standard deviations (Choose one) ▼ the mean exam score among all students in the course. Calendar ... 80 F3 F4 F6 F7 F8 F9 F10 F11 云

2000 freshmen at state university took a biology test. the scores were normally distributed with a mean of 70 and a standard deviation of 5. Use z scores. (1) the percent of students that scored less than 77
Deanna is the principal at a Midwestern middle school and wants to know the average IQ of all female, seventh grade students. She does not know anything about what the population distribution looks like. She took a simple random sample of 31 seventh-grade girls in her school and found the average IQ score in her sample was 105.8 and the standard deviation was 15. Using the sample standard deviation above to estimate the population standard deviation, what is the minimum sample size needed for a 99.5% confidence interval to have a margin of error of no more than 2.3?

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS