/*! 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.3  Strong chairs? A company that ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Strong chairs? A company that manufactures classroom chairs for high school students claims that the mean breaking strength of the chairs that they make is 300pounds. One of the chairs collapsed beneath a 220-pound student last week. You wonder whether the manufacturer is exaggerating the breaking strength of the chairs.

(a) State null and alternative hypotheses in words and symbols.

(b) Describe a Type I error and a Type II error in this situation, and give the consequences of each.

(c) Would you recommend a significance level of0.01,0.05, or 0.10for this test? Justify your choice.

(d) The power of this test to detect μ=294is 0.71. Explain what this means to someone who knows little statistics.

(e) Explain two ways that you could increase the power of the test from (d).

- If conditions are met, conduct a significance test about a population proportion.

Short Answer

Expert verified

(a) Null hypothesisH0:μ=300

Alternative hypothesis H1:μ<300H1:μ<300

(b)The type l error occurs whenH0 is rejected when H0is the true solution.

Type ll errors imply that the chair is more likely to collapse.

(c) We can choose significance level 0.10, because this is the greatest value out of the given values 0.01,0.05,0.10.

(d)When μ=294, the power of the test is0.71, which means the probability of rejecting the null hypothesis is0.71

(e) Increase the size and the level of significance

Step by step solution

01

Part (a) Step 1: Given Information

Given In the question that the company that manufactures classroom chairs for high school students claims that the mean breaking strength of the chairs that they make is 3 pounds. One of the chairs collapsed beneath a 220-pound student last week. You wonder whether the manufacturer is exaggerating the breaking strength of the chairs. we have to State null and alternative hypotheses in words and symbol. we have to State null and alternative hypotheses in words and symbols.

02

Part (a) Step 2: Explanation

For high school students, a manufacturer makes classroom chairs. The chairs' average breaking strength is 300pounds. One of the chairs, weighing 220pounds, collapsed.

Let μrepresent the chair's strength.

The null hypothesis is the one that is thought to be correct. H0is the symbol for it.

Determine what the null hypothesis is. H0:μ=300

One of the seats, weighing less than300pounds, gave apart.

Create an alternative hypothesis.H1:μ<300.

03

Part (b) Step 1: Given Information

Given In the question that the company that manufactures classroom chairs for high school students claims that the mean breaking strength of the chairs that they make is 300pounds. One of the chairs collapsed beneath a 220-pound student last week. You wonder whether the manufacturer is exaggerating the breaking strength of the chairs. we have to State null and alternative hypotheses in words and symbol. we have to describe a Type I error and a Type II error in this situation, and give the consequences of each.

04

Part (b) Step 2: Explanation

When H0is rejected, it is referred to as a Type I error. H0:μ=300is the null hypothesis.

The chair's mean breaking strength is 300pounds.

The Type Il error occurs when H0is accepted when H0is false.

H1:μ<300is an alternative hypothesis.

This means the chair's mean breaking strength is less than 300pounds.

Type II errors in the provided problem imply that collapsing a chair is unlikely.

The type Il mistake indicates that the likelihood of the chair collapsing is greater.

05

Part (c) Step 1: Given Information

Given in the question that there are 3significane levels .01,0.05,0.10. we have to find out that which one is recommended for the test.

06

Part (c) Step 2: Explanation 

The three levels of significance are0.01,0.05and0.10, respectively.

When H0is true and H0is rejected, it is referred to as a Type I error.

H0:μ=300is the null hypothesis.

When H0is accepted when H0is false, this is known as a Type II error.

H1:μ<300is an alternat ve hypothesis.

Type I errors imply that the chair will collapse less in response to the provided situation.

The Type Il fault means the chair will collapse more frequently.

The major goal is to keep Type II errors to a minimum

because they are more dangerous.

This occurs when the Type I mistake αis higher.

The value also deαnotes the significance level.

0.01,0.02,0.10are the specified values.

We can choose significance level 0.10, because this is the greatest value out of the given values .

07

Part (d) Step 1: Given Information 

Given in the question that the power of this test to detect μ=294is 0.71we have to explain what this means to someone who knows little statistics.

08

Part (d) Step 2: Explanation 

H0:μ=300is the null hypothesis.

H1:μ<300is an alternative hypothesis.

The test's power to detect μ=294is0.71. Test power is defined as the chance of rejecting the null hypothesis if the alternative hypothesis is true.

When μ=294, the test's power is 0.71, which means the chance of rejecting the null hypothesis is 0.71.

09

Part (e) Step 1: Given Information 

We have to explain two ways that you could increase the power of the test from (d).

10

Part (e) Step 2: Explanation 

1. Increase the sample size: A larger sample size allows for more accurate estimation.

2. Increase the level of significance: This will increase the probability of making a Type I error, lowering the chances of making a Type II error. As a result, it will increase the test's power by definition.

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 91Ó°ÊÓ!

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

An opinion poll asks a random sample of adults whether they favor banning ownership of handguns by private citizens. A commentator believes that more than half of all adults favor such a ban. The null and alternative hypotheses you would use to test this claim are

a).H0:p^=0.5;Ha:p^>0.5

(b) H0:p=0.5;Ha:p>0.5

(c) H0:p=0.5;Ha:p<0.5

(d) H0:p=0.5;Ha:p≠0.5

(e) H0:p>0.5;Ha:p=0.5

Explain in plain language why a significance test that is significant at the 1% level must always be significant at the 5% level. If a test is significant at the 5% level, what can you say about its significance at the 1% level?

Attitudes The Survey of Study Habits and Attitudes (SSHA) is a psychological test that measures students’ attitudes toward school and study habits. Scores range from 0to200. The mean score for U.S. college students is about 115. A teacher suspects that

older students have better attitudes toward school. She gives the SSHA to an SRS of 45of the over 1000students at her college who are at least 30years of age. Check the conditions for carrying out a significance test of the teacher’s suspicion.

After checking that conditions are met, you perform a significance test of H0:μ=1versus Hα:μ≠1. You obtain a Pvalue of 0.022. Which of the following is true?

(a) A95%confidence interval for μwill include the value 1

(b) A 95%confidence interval forμwill include the value 0.

(c) A99% confidence interval forμwill include the value 1

(d) A 99%confidence interval for μwill include the value 0

(e) None of these is necessarily true.

Are TV commercials louder than their surrounding programs? To find out, researchers collected data on 50randomly selected commercials in a given week. With the television’s volume at a fixed setting, they measured the maximum loudness of each commercial and the maximum loudness in the first 30seconds of regular programming that followed. Assuming conditions for inference are met, the most appropriate method for answering the question of interest is

(a) a one-proportion z test.

(b) a one-proportion z interval.

(c) a paired t test.

See all solutions

Recommended explanations on Math Textbooks

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.