420Hw01 - STAT 420 Fall 2010 Homework #1 (10 points) (due...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
STAT 420 Fall 2010 Homework #1 (10 points) (due Friday, September 3, by 3:00 p.m.) 1. 3.5 The salary of junior executives in a large retailing firm is normally distributed with standard deviation σ = $1,500. If a random sample of 25 junior executives yields an average salary of $16,400, what is the 95-percent confidence interval for μ , the average salary of all junior executives. 2. 3.12 Redo Problem 3.5 without assuming that the population standard deviation is known. You are given s = $1,575.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3. A coffee machine is regulated so that the amount of coffee dispensed is normally distributed. A random sample of 17 cups had an average of 7.91 ounces per cup and a sample standard deviation of 0.175 ounces. a) Construct a 90% confidence interval for the overall average amount of coffee dispensed by the machine. b) The coffee machine manufacturer claims that the overall average amount of coffee dispensed is at least 8 ounces. Find the P-value of the test H 0 : μ = 8 vs. H 1 : μ < 8. c)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/17/2010 for the course STAT 420 taught by Professor Stepanov during the Spring '08 term at University of Illinois, Urbana Champaign.

Page1 / 3

420Hw01 - STAT 420 Fall 2010 Homework #1 (10 points) (due...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online