/*! 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 5. Don鈥檛 drink the water!聽The mo... [FREE SOLUTION] | 91影视

91影视

Don鈥檛 drink the water!The movie A Civil Action (1998) tells the story of a

major legal battle that took place in the small town of Woburn, Massachusetts. A town well that supplied water to east Woburn residents was contaminated by industrial chemicals. During the period that residents drank water from this well, 16of 414babies born had birth defects. On the west side of Woburn, 3of 228babies born during the same time period had birth defects. Let p1be

the true proportion of all babies born with birth defects in west Woburn and p2be the true proportion of all babies born with birth defects in east Woburn. Check if the conditions for calculating a confidence interval forp1-p2are met.

Short Answer

Expert verified

It is not fit to find confidence interval forp1-p2

Step by step solution

01

Given Information

It is given that n1=414

x1=16

n2=228

x2=3

02

Explanation

Testing three conditions:

1. Random: As it is arbitrarily assigned, it is not met.

2. Independent: Due to used all values in population and not used sample, it is not satisfied.

3. Normal: There are only three success which is less than ten.

All conditions are not satisfied, it is not fit to find confidence intervalp1-p2

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

Sports Illustrated planned to ask a random sample of Division I college athletes, 鈥淒o you believe performance-enhancing drugs are a problem in college sports?鈥 Which of the following is the smallest number of athletes that must be interviewed to estimate the true proportion who believe performance-enhancing drugs are a problem within 2% with 90% confidence?

a.17b.21c.1680d.1702e.2401

Starting in the 1970s, medical technology has enabled babies with very low birth weight (VLBW, less than1500grams, or about 3.3 pounds) to survive without major handicaps. It was noticed that these children nonetheless had difficulties in school and as adults. A long-term study has followed 242 randomly selected VLBW babies to age 20years, along with a control group of 233 randomly selected babies from the same population who had normal birth weight. 50

a. Is this an experiment or an observational study? Why?

b. At age20,179 of the VLBW group and 193 of the control group had graduated from high school. Do these data provide convincing evidence at the 伪=0.05 significance level that the graduation rate among VLBW babies is less than for normal-birth-weight babies?

Broken crackers We don鈥檛 like to find broken crackers when we open the package. How can makers reduce breaking? One idea is to microwave the crackers for 30seconds right after baking them. Randomly assign 65newly baked crackers to the microwave and another 65to a control group that is not microwaved. After 1day, none of the microwave group were broken and 16of the control group were broken. Let p1be the true proportions of crackers like these that would break if baked in the microwave and p2be the true proportions of crackers like these that would break if not microwaved. Check if the conditions for calculating a confidence interval forp1-p2met.

Each day I am getting better in math A "subliminal" message is below our threshold of awareness but may nonetheless influence us. Can subliminal messages help students learn math? A group of 18students who had failed the mathematics part of the City University of New York Skills Assessment Test agreed to participate in a study to find out. All received a daily subliminal message, flashed on a screen too rapidly to be consciously read. The treatment group of 10students (assigned at random) was exposed to "Each day I am getting better in math." The control group of 8students was exposed to a neutral message, "People are walking on the street." All 18students participated in a summer program designed to improve their math skills, and all took the assessment test again at the end of the program. The following table gives data on the subjects' scores before and after the program.

a. Explain why a two-sample t-test and not a paired t-test is the appropriate inference procedure in this setting.

b. The following boxplots display the differences in pretest and post-test scores for the students in the control (C) and treatment (T) groups. Write a few sentences comparing the performance of these two groups.

c. Do the data provide convincing evidence at the =0.01,3051526=0.200=20%significance level that subliminal messages help students like the ones in this study learn math, on average?

d. Can we generalize these results to the population of all students who failed the mathematics part of the City University of New York Skills Assessment Test? Why or why not?

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鈥檚 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 two-sample t test for a difference in means.

b. a two-sample t interval for a difference in means.

c. a paired t test for a mean difference.

d. a paired t interval for a mean difference.

e. a two-sample z test for a difference in proportions.

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.