Assignment Task
Question 1 Heights for 8 year old girls are normally distributed with a mean of 127 cm and a standard deviation of 3 cm.
a) Sketch the normal model for the girls’ heights.
Need Help Writing an Essay?
Tell us about your assignment and we will find the best writer for your paper.
Get Help Now!b) In what interval would you expect the central 95% of heights to lie?
c) What percentage of the girls are taller than 131 cm?
d) Below what height are the shortest 25% of girls?
e) If 15 girls are randomly selected, find the probability that their average height is greater than 129 cm.
Question 2 The recommended amount of sleep for young adults is 7 to 9 hours per night. A random sample of 30 university students reported a mean nightly sleep time of 6.53 hours and standard deviation of 1.12 hours.
a) Using a suitable hypothesis test procedure, test the hypothesis that university students are not meeting the minimum sleep requirement. Use α = 0.05 and include all the steps.
b) Calculate a 90% confidence interval for the true mean amount of sleep, and interpret the interval.
c) Comment on the hypothesis test conclusion from part a) in relation to the confidence interval found in part b).
Welcome to Our Online Academic Writing Service. Our online assignment writing website provide various guarantees that will never be broken. No matter whether you need a narrative essay, 5-paragraph essay, persuasive essay, descriptive essay, or expository essay, we will provide you with quality papers at student friendly price.
Ask for Instant Writing Help. No Plagiarism Guarantee!


