/*! 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 61. Critical values What critical va... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 8: Q 61. (page 541)

Critical values What critical value t*from Table B should be used for a

confidence interval for the population mean in each of the following situations?

a. A 95% confidence interval based on n=10 randomly selected observations

b. A99% confidence interval from an SRS of 20 observations

c. A 90% confidence interval based on a random sample of 77 individuals

Short Answer

Expert verified

a. The critical value is 2.262

b. The critical value is 2.861

c. The critical value is1.671

Step by step solution

01

Part (a) Step 1: Given Information

It is given that Confidence Level =95%

n=10

02

Part (a) Step 2: Calculation

Level of significance, (伪)=1-0.95=0.05

Degree of df=n-1

=10-1=9

At 5%, level of significance

t伪/2,df=z0.05/2,9=2.262

The critical value is2.262

03

Part (b) Step 1: Given Information

It is given that Confidence Level =99%

n=20

04

Part (b) Step 2: Calculation

Level of Significance, (伪)=1-0.99=0.01

Degree of freedom, df=n-1

=20-1=19

At 1%level of significance,

t伪/2,df=t0.01/2,19=2.861

The critical value is2.861

05

Part (c) Step 5: Given Infromation

It is given that Confidence Level =90%

n=77

06

Part (c) Step 2: Calculation

Level of significance, (伪)=1-0.90=0.10

Degree of freedom, df=n-1

=77-1=76

At 10%level of significance, critical value is

t伪/2,df=t0.10/2,76=1.671

The critical value is1.671

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

September 11 A recent study asked U.S. adults to name 10historic events that occurred in their lifetime that have had the greatest impact on the country. The most frequently chosen answer was the September 11,2001, terrorist attacks, which was included by 76%of the 2025randomly selected U.S. adults. Construct and interpret a 95%confidence interval for the proportion of all U.S. adults who would include the 9/11attacks on their list of 10historic events.

Three branches According to a recent study by the Annenberg Foundation, only 36%of adults in the United States could name all three branches of government. This was based on a survey given to a random sample of1416U.S. adults.

a. Construct and interpret a 90%confidence interval for the proportion of all U.S. adults who could name all three branches of government.

b. Does the interval from part (a) provide convincing evidence that less than half of all U.S. adults could name all three branches of government? Explain your answer.

A school of fish Refer to Exercise 74.

a. Explain why it was necessary to inspect a graph of the sample data when checking the Normal/Large Sample condition.

b. According to the packaging, there are supposed to be 330goldfish in each bag of crackers. Based on the interval, is there convincing evidence that the average number of goldfish is less than 330? Explain your answer.

Lying online Many teens have posted profiles on sites such as Facebook. A sample survey asked random samples of teens with online profiles if they included false information in their profiles. Of 170younger teens (ages role="math" localid="1654194610029" 12to14) polled, 117said 鈥淵es.鈥� Of 317older teens (ages 15to17) polled, 152said 鈥淵es.鈥� A 95%confidence interval for pY-pO=the true difference in the proportions of younger teens and older teens who include false information in their profile is 0.120to 0.297.

a. Interpret the confidence interval.

b. Does the confidence interval give convincing evidence of a difference in the true

proportions of younger and older teens who include false information in their profiles?

Explain your answer.

10Bottling cola A particular type of diet cola advertises that each can contains 12 ounces of the beverage. Each hour, a supervisor selects cans at random, measures their contents, and computes a 95%confidence interval for the true mean volume. For one particular hour, the 95%confidence interval is 11.97ounces to 12.05ounces.

a. Does the confidence interval provide convincing evidence that the true mean volume is different than 12ounces? Explain your answer.

b. Does the confidence interval provide convincing evidence that the true mean volume is 12ounces? Explain your answer.
See all solutions

Recommended explanations on Math Textbooks

Applied Mathematics

Read Explanation

Statistics

Read Explanation

Calculus

Read Explanation

Decision Maths

Read Explanation

Pure Maths

Read Explanation

Theoretical and Mathematical Physics

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.