/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q.96 Announcements for 84 upcoming en... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 8: Q.96 (page 483)

Announcements for 84 upcoming engineering conferences were randomly picked from a stack of IEEE Spectrum

magazines. The mean length of the conferences was 3.94 days, with a standard deviation of 1.28 days. Assume the

underlying population is normal.

a. In words, define the random variables X and X

b. Which distribution should you use for this problem? Explain your choice.

c. Construct a 95% confidence interval for the population mean length of engineering conferences.

I. State the confidence interval.

ii. Sketch the graph.

iii. Calculate the error bound.

Short Answer

Expert verified

a. The average length of an engineering conference is X, while the mean length of 84 engineering conferences is X

b. Normal distribution

c. I. CI-(3.663, 4.2137)

ii.

iii. EBM = 0.2737 2

Step by step solution

01

Explanation of A

The average length of an engineering conference is X, while the mean length of 84 engineering conferences is X.

02

Explanation of B

The normal distribution should be for the problem N3.94,1.2884, we know that the sample size for the population's standard deviation is bigger than 30.

03

Explanation of C

I.State the confidence interval

CI-(3.6663,4.2137)

ii.The graph is given below,

iii.The error bound is calculated from the formula,

EBM = upperlimit-lowerlimit2

EBM =4.21373.66632

EBM=0.27372

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A sample of 20heads of lettuce was selected. Assume that the population distribution of head weight is normal. The weight of each head of lettuce was then recorded. The mean weight was 2.2pounds with a standard deviation of 0.1pounds. The population standard deviation is known to be 0.2pounds.

Identify the following:

a. x炉=

b. 蟽=

C. n=

Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to estimate its mean number of unoccupied seats per flight over the past year. To accomplish this, the records of 225 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.6 seats and the sample standard deviation is 4.1 seats.

a. i. x=__________

ii. sx=__________

iii. n=__________

iv. n-1=__________

b. Define the random variables Xand Xin words.

c. Which distribution should you use for this problem? Explain your choice.

d. Construct a 92% confidence interval for the population mean number of unoccupied seats per flight.

i. State the confidence interval.

ii. Sketch the graph.

iii. Calculate the error bound.

A camp director is interested in the mean number of letters each child sends during his or her camp session. The

population standard deviation is known to be 2.5. A survey of 20campers is taken. The mean from the sample is 7.9with a

sample standard deviation of 2.8.

a.

localid="1651507797100" i.x虅=________ii.蟽=________iii.n=________

b. Define the random variables XandX虅

in words.

c. Which distribution should you use for this problem? Explain your choice.

d. Construct a 90%confidence interval for the population mean number of letters campers send home.

i. State the confidence interval.

ii. Sketch the graph.

iii. Calculate the error bound.

e. What will happen to the error bound and confidence interval if 500campers are surveyed? Why?

Identify the following:

a. x=_______

b. sx =_______

c. n =_______

d. n 鈥� 1 =_______

Suppose that a committee is studying whether or not there is waste of time in our judicial system. It is interested in

the mean amount of time individuals waste at the courthouse waiting to be called for jury duty. The committee randomly

surveyed 81people who recently served as jurors. The sample mean wait time was eight hours with a sample standard

deviation of four hours.

a.i.x虅=__________ii.sx=__________iii.n=__________iv.n鈥�1=__________

b. Define the random variables XandX虅in words.

c. Which distribution should you use for this problem? Explain your choice.

d. Construct a 95%confidence interval for the population mean time wasted.

i. State the confidence interval.

ii. Sketch the graph.

iii. Calculate the error bound.

e. Explain in a complete sentence what the confidence interval means.
See all solutions

Recommended explanations on Math Textbooks

Geometry

Read Explanation

Mechanics Maths

Read Explanation

Calculus

Read Explanation

Logic and Functions

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Applied Mathematics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.