/*! 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. 2.1 To introduce her class to binomi... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 6: Q. 2.1 (page 390)

To introduce her class to binomial distributions, Mrs. Desai gives a 10 -item, multiple-choice quiz. The catch is, that students must simply guess an answer (A through E) for each question. Mrs. Desai uses her computer's random number generator to produce the answer key so that each possible answer has an equal chance to be chosen. Patti is one of the students in this class. Let X=the number of Patti's correct guesses.

1. Show that Xis a binomial random variable.

Short Answer

Expert verified

It has been shown thatXis a binomial random variable.

Step by step solution

01

Given Information 

Mr. Desai gives =10times

X=The number of Patti's correct guesses.

02

Explanation

The algorithm chose correct responses at random, thus one trial should not alter the outcome of the others.

There were ten questions in total.

Each trial has a0.20 chance of succeeding.

As a result, this is a binomial situation.

Because it counts the number of successes, Xis a binomial random variable withn=10and p=0.20.

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

81. Random digit dialing When an opinion poll calls residential telephone numbers at random, only20% of the calls reach a live person. You watch the random digit dialing machine make 15 calls. Let X= the number of calls that reach a live person.
(a) Find and interpret 渭X.
(b) Find and interpret 蟽X.

18. Life insurance

(a) It would be quite risky for you to insure the life of a 21-year-old friend under the terms of Exercise 14. There is a high probability that your friend would live and you would gain \(1250in premiums. But if he were to die, you would lose almost \)100,000. Explain carefully why selling insurance is not risky for an insurance company that insures many thousands of 21-year-old men.

(b) The risk of an investment is often measured by the standard deviation of the return on the investment. The more variable the return is, the riskier the
investment. We can measure the great risk of insuring a single person鈥檚 life in Exercise 14by computing the standard deviation of the income Y that the insurer will receive. Find 蟽Y using the distribution and mean found in Exercise 14.

Predicting posttest scores(3.2) What is the equation of the linear regression model relating posttest and pretest scores? De铿乶e any variables used.

Friends How many close friends do you have? An opinion poll asks this question of an SRS of 1100 adults. Suppose that the number of close friends adults claim to have varies from person to person with mean 渭=9 and standard deviation 蟽=2.5. We will see later that in repeated random samples of size 1100, the mean response x will vary according to the Normal distribution with mean 9 and standard deviation 0.075. What is role="math" localid="1649504967961" P(8.9鈮�x鈮�9.1), the probability that the sample result x estimates the population truth 渭=9 to within 卤0.1?

Fire insurance Suppose a homeowner spends \(300for a home insurance policy that will pay out \)200,000if the home is destroyed by fire. Let Y=the profit made by the company on a single policy. From previous data, the probability that a home in this area will be destroyed by fire is 0.0002.

(a) Make a table that shows the probability distribution of Y.

(b) Compute the expected value of Y. Explain what this result means for the insurance company
See all solutions

Recommended explanations on Math Textbooks

Theoretical and Mathematical Physics

Read Explanation

Calculus

Read Explanation

Statistics

Read Explanation

Geometry

Read Explanation

Applied Mathematics

Read Explanation

Pure Maths

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.