/*! 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. 45 Ms. Hall gave her class a 10-que... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Ms. Hall gave her class a 10-question multiple-choice quiz.

Let X=the number of questions that a randomly selected student in the class answered correctly. The computer output gives information about the probability distribution of X. To determine each student’s grade on the quiz (out of 100), Ms. Hall will multiply his or her number of correct answers by 5and then add 50.Let G=the grade of a randomly chosen student in the class.

Easy quiz

a. Find the median of G.

b. Find the interquartile range (IQR) of G.

Short Answer

Expert verified

a. The median is 92.5.

b. Interquartile range for G is5.

Step by step solution

01

Part(a) Step 1 : Given Information    

Given :

X=the number of questions that a randomly selected student in the class answered correctly.

Ms. Hall multiplies his or her number of correct answers by 5and then add 50.

G=the grade of a randomly chosen student in the class.

02

Part(a) Step 2 : Simplification   

The grade is calculated by multiplying the number of right answers by 5and increasing by 50.

G=5X+50

This means that each data value in the Xdistribution is multiplied by the same constant 5and then multiplied by the same constant 50.

When the same constant is applied to each data value, the center of the distribution is also enlarged by the same constant.

Furthermore, if every data value is multiplied by the same constant, the distribution's center is multiplied by the same constant.

The median is the center's measurement, as we all know.

As a result, the median is :

Med.G=5Med.X+50=5(8.5)+50=92.5

03

Part(b) Step 1 : Given Information    

Given :

X= the number of questions that a randomly selected student in the class answered correctly.

Ms. Hall multiplies his or her number of correct answers by 5and then add 50.

G=the grade of a randomly chosen student in the class.

04

Part(b) Step 2 : Simplification   

IQRX=Q1-Q1=9-8=1is the interquartile range for X. The grade is calculated by multiplying the number of right answers by 5and increasing by 50.

5X+50=G

This means that each data value in the Xdistribution is multiplied by the same constant 5 and then multiplied by the same constant 50. The spread of the distribution is unaltered if every data value is multiplied by the same constant.

Furthermore, if every data value is multiplied by the same constant, the distribution's spread is also multiplied by the same constant. The interquartile range (IQR) is a measure of the spread, as we all know. As a result, double the interquartile range (IQR) by 5.

Thus,

IQRG=5(IQRX)=5(1)=5interquartile range for G

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

Geometric or not? Determine whether each of the following scenarios describes a geometric setting. If so, define an appropriate geometric random variable.

a. Shuffle a standard deck of playing cards well. Then turn over one card at a time from the top of the deck until you get an ace.

b. Billy likes to play cornhole in his free time. On any toss, he has about a 20%chance of getting a bag into the hole. As a challenge one day, Billy decides to keep tossing bags until he gets one in the hole.

Swim team Hanover High School has the best women's swimming team in the region. The 400meter freestyle relay team is undefeated this year. In the 400-meter freestyle relay, each swimmer swims 100meters. The times, in seconds, for the four swimmers this season are approximately Normally distributed with means and standard deviations as shown. Assuming that the swimmer's individual times are independent, find the probability that the total team time in the 400meter freestyle relay is less than 220seconds.follow the four step process.

SwimmerMeanStd.dev
Wendy55.22.8
Jill58.03.0
Carmen56.32.6
Latrice54.72.7

Life insurance A life insurance company sells a term insurance policy to 21-year-old males that pays \(100,000 if the insured dies within the next 5 years. The probability that a randomly chosen male will die each year can be found in mortality tables. The company collects a premium of \)250 each year as payment for the insurance. The amount Y that the company earns on a randomly selected policy of this type is \(250 per year, less the \)100,000 that it must pay if the insured dies. Here is the probability distribution of Y:

(a) Explain why the company suffers a loss of $98,750 on such a policy if a client dies at age 25.

(b) Calculate the expected value of Y. Explain what this result means for the insurance company.

(c) Calculate the standard deviation of Y. Explain what this result means for the insurance company.

Lie detectors A federal report finds that lie detector tests given to truthful persons have probability 0.2 of suggesting that the person is deceptive. 11 A company asks 12 job applicants about thefts from previous employers, using a lie detector to assess their truthfulness. Suppose that all 12 answer truthfully. Let Y= the number of people whom the lie detector indicates are being deceptive.

a. Find the probability that the lie detector indicates that at least 10 of the people are being honest.

b. Calculate and interpret μYμY.

c. Calculate and interpret σYσY.

Red light! Pedro drives the same route to work on Monday through Friday. His route includes one traffic light. According to the local traffic department, there is a 55%chance

that the light will be red on a randomly selected work day. Suppose we choose 10 of Pedro's work days at random and let Y= the number of times that the light is red. Make a graph of the probability distribution of Y . Describe its shape.

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.