Understandable Statistics: Concepts and Methods
Understandable Statistics: Concepts and Methods
12th Edition
ISBN: 9781337119917
Author: Charles Henry Brase, Corrinne Pellillo Brase
Publisher: Cengage Learning
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 6.3, Problem 39P

(a)

To determine

Find the probability that the waiting time would exceed 20 minutes, given that it has exceeded 15 minutes.

(a)

Expert Solution
Check Mark

Answer to Problem 39P

The probability that the waiting time would exceed 20 minutes, given that it has exceeded 15 minutes is 0.3989.

Explanation of Solution

Calculation:

Z score:

The number of standard deviations the original measurement x is from the value of mean μ is measured using the z-score or z value. The formula for z score is,

z=xμσ

In the formula, x is the raw score, μ is the mean and σ is the standard deviation.

The conditional probability formula is,

P(A|B)=P(A and B)P(B)

The variable x denotes the length of time waiting to be seated.

The probability that the waiting time would exceed 20 minutes, given that it has exceeded 15 minutes is,

P(x>20|x>15)=P(x>20 and x>15)P(x>15)=P(x>20)P(x>15)

For P(x>20):

Substitute x as 20, μ as 18 and σ as 4 in the formula of z score.

z=20184=24=0.5

Use the Appendix II: Tables, Table 5: Areas of a Standard Normal Distribution: to obtain probability less than 0.5.

  • Locate the value 0.5 in column z.
  • Locate the value 0.00 in top row.
  • The intersecting value of row and column is 0.6915.

The probability is,

P(x>20)=P(z>0.5)=1P(z<0.5)=10.6915=0.3085

For P(x>15):

Substitute x as 15, μ as 18 and σ as 4 in the formula of z score.

z=15184=34=0.75

Use the Appendix II: Tables, Table 5: Areas of a Standard Normal Distribution: to obtain probability less than –0.75.

  • Locate the value –0.7 in column z.
  • Locate the value 0.05 in top row.
  • The intersecting value of row and column is 0.2266.

The probability is,

P(x>15)=P(z>0.75)=1P(z<0.75)=10.2266=0.7734

Substituting 0.3085 for P(x>20) and 0.7734 for P(x>15) in the required probability:

P(x>20|x>15)=0.30850.7734=0.3989

Hence, the probability that the waiting time would exceed 20 minutes, given that it has exceeded 15 minutes is 0.3989.

(b)

To determine

Find the probability that the waiting time would exceed 25 minutes, given that it has exceeded 18 minutes.

(b)

Expert Solution
Check Mark

Answer to Problem 39P

The probability that the waiting time would exceed 25 minutes, given that it has exceeded 18 minutes is 0.0802.

Explanation of Solution

Calculation:

The probability that the waiting time would exceed 25 minutes, given that it has exceeded 18 minutes is,

P(x>25|x>18)=P(x>25 and x>18)P(x>18)=P(x>25)P(x>18)

For P(x>25):

Substitute x as 25, μ as 18 and σ as 4 in the formula of z score.

z=25184=74=1.75

Use the Appendix II: Tables, Table 5: Areas of a Standard Normal Distribution: to obtain probability less than 1.75.

  • Locate the value 1.7 in column z.
  • Locate the value 0.05 in top row.
  • The intersecting value of row and column is 0.9599.

The probability is,

P(x>25)=P(z>1.75)=1P(z<1.75)=10.9599=0.0401

For P(x>18):

Substitute x as 18, μ as 18 and σ as 4 in the formula of z score.

z=18184=04=0

Use the Appendix II: Tables, Table 5: Areas of a Standard Normal Distribution: to obtain probability less than 0.

  • Locate the value 0.0 in column z.
  • Locate the value 0.00 in top row.
  • The intersecting value of row and column is 0.5000.

The probability is,

P(x>18)=P(z>0)=1P(z<0)=10.5=0.5

Substituting 0.0401 for P(x>25) and 0.5 for P(x>18) in the required probability:

P(x>25|x>18)=0.04010.5=0.0802

Hence, the probability that the waiting time would exceed 25 minutes, given that it has exceeded 18 minutes is 0.0802.

(c)

To determine

Show that P(x>20|x>15)=P(x>20)P(x>15).

(c)

Expert Solution
Check Mark

Explanation of Solution

Calculation:

Take event A as x>20 and event B as x>15 in the conditional probability formula.

P(x>20|x>15)=P(x>20 and x>15)P(x>15)

It is clear that the x is greater than 20 and x is greater than 15 this implies that the value of x is greater than 20. That is,

P(x>20|x>15)=P(x>20)P(x>15)

Hence, it is shown that P(x>20|x>15)=P(x>20)P(x>15).

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
An Arts group holds a raffle.  Each raffle ticket costs $2 and the raffle consists of 2500 tickets.  The prize is a vacation worth $3,000.    a. Determine your expected value if you buy one ticket.     b. Determine your expected value if you buy five tickets.     How much will the Arts group gain or lose if they sell all the tickets?
Please show as much work as possible to clearly show the steps you used to find each solution. If you plan to use a calculator, please be sure to clearly indicate your strategy.        Consider the following game.  It costs $3 each time you roll a six-sided number cube.  If you roll a 6 you win $15.  If you roll any other number, you receive nothing.   a) Find the expected value of the game.         b) If you play this game many times, will you expect to gain or lose money?
= 12:02 WeBWorK / 2024 Fall Rafeek MTH23 D02 / 9.2 Testing the Mean mu / 3 38 WEBWORK Previous Problem Problem List Next Problem 9.2 Testing the Mean mu: Problem 3 (1 point) Test the claim that the population of sophomore college students has a mean grade point average greater than 2.2. Sample statistics include n = 71, x = 2.44, and s = 0.9. Use a significance level of a = 0.01. The test statistic is The P-Value is between : The final conclusion is < P-value < A. There is sufficient evidence to support the claim that the mean grade point average is greater than 2.2. ○ B. There is not sufficient evidence to support the claim that the mean grade point average is greater than 2.2. Note: You can earn partial credit on this problem. Note: You are in the Reduced Scoring Period. All work counts for 50% of the original. Preview My Answers Submit Answers You have attempted this problem 0 times. You have unlimited attempts remaining. . Oli wwm01.bcc.cuny.edu

Chapter 6 Solutions

Understandable Statistics: Concepts and Methods

Ch. 6.1 - Pain Management: Laser Therapy Effect of...Ch. 6.1 - Control Charts: Yellowstone National Park...Ch. 6.1 - Control Charts: Bank Loans Tri-County Bank is a...Ch. 6.1 - Control Charts: Motel Rooms The manager of Motel...Ch. 6.1 - Prob. 15PCh. 6.1 - Prob. 16PCh. 6.1 - Uniform Distribution: Measurement Errors...Ch. 6.1 - Prob. 18PCh. 6.1 - Prob. 19PCh. 6.1 - Prob. 20PCh. 6.2 - Statistical Literacy What does a standard score...Ch. 6.2 - Statistical Literacy Does a raw score less than...Ch. 6.2 - Prob. 3PCh. 6.2 - Prob. 4PCh. 6.2 - Basic Computation: z Score and Raw Score A normal...Ch. 6.2 - Basic Computation: z Score and Raw Score A normal...Ch. 6.2 - Prob. 7PCh. 6.2 - Prob. 8PCh. 6.2 - z Scores: First Aid Course The college physical...Ch. 6.2 - Prob. 10PCh. 6.2 - Prob. 11PCh. 6.2 - Normal Curve: Tree Rings Tree-ring dates were used...Ch. 6.2 - Basic Computation: Finding Areas Under the...Ch. 6.2 - Prob. 14PCh. 6.2 - Basic Computation: Finding Areas Under the...Ch. 6.2 - Prob. 16PCh. 6.2 - Prob. 17PCh. 6.2 - Prob. 18PCh. 6.2 - Prob. 19PCh. 6.2 - Basic Computation: Finding Areas Under the...Ch. 6.2 - Prob. 21PCh. 6.2 - Prob. 22PCh. 6.2 - Prob. 23PCh. 6.2 - Prob. 24PCh. 6.2 - Prob. 25PCh. 6.2 - Prob. 26PCh. 6.2 - Prob. 27PCh. 6.2 - Prob. 28PCh. 6.2 - Prob. 29PCh. 6.2 - Basic Computation: Finding Areas Under the...Ch. 6.2 - Prob. 31PCh. 6.2 - Prob. 32PCh. 6.2 - Basic Computation: Finding Probabilities In...Ch. 6.2 - Prob. 34PCh. 6.2 - Prob. 35PCh. 6.2 - Prob. 36PCh. 6.2 - Prob. 37PCh. 6.2 - Basic Computation: Finding Probabilities In...Ch. 6.2 - Prob. 39PCh. 6.2 - Prob. 40PCh. 6.2 - Prob. 41PCh. 6.2 - Prob. 42PCh. 6.2 - Basic Computation: Finding Probabilities In...Ch. 6.2 - Prob. 44PCh. 6.2 - Basic Computation: Finding Probabilities In...Ch. 6.2 - Prob. 46PCh. 6.2 - Prob. 47PCh. 6.2 - Basic Computation: Finding Probabilities In...Ch. 6.2 - Prob. 49PCh. 6.2 - Prob. 50PCh. 6.3 - Statistical Literacy Consider a normal...Ch. 6.3 - Statistical Literacy Suppose 5% of the area under...Ch. 6.3 - Prob. 3PCh. 6.3 - Critical Thinking: Normality Consider the...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find Probabilities In Problems...Ch. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Prob. 20PCh. 6.3 - Prob. 21PCh. 6.3 - Basic Computation: Find z Values In Problems 1524,...Ch. 6.3 - Prob. 23PCh. 6.3 - Prob. 24PCh. 6.3 - Prob. 25PCh. 6.3 - Prob. 26PCh. 6.3 - Archaeology: Hopi Village Thickness measurements...Ch. 6.3 - Law Enforcement: Police Response Time Police...Ch. 6.3 - Prob. 29PCh. 6.3 - Guarantee: Watches Accrotime is a manufacturer of...Ch. 6.3 - Expand Your Knowledge: Estimating the Standard...Ch. 6.3 - Estimating the Standard Deviation: Refrigerator...Ch. 6.3 - Prob. 33PCh. 6.3 - Prob. 34PCh. 6.3 - Insurance: Satellites A relay microchip in a...Ch. 6.3 - Convertion Center: Exhibition Show Attendance...Ch. 6.3 - Exhibition Shows: Inverse Normal Distribution Most...Ch. 6.3 - Budget: Maintenance The amount of money spent...Ch. 6.3 - Prob. 39PCh. 6.3 - Prob. 40PCh. 6.4 - Prob. 1PCh. 6.4 - Prob. 2PCh. 6.4 - Prob. 3PCh. 6.4 - Prob. 4PCh. 6.4 - Prob. 5PCh. 6.4 - Prob. 6PCh. 6.4 - Prob. 7PCh. 6.4 - Prob. 8PCh. 6.4 - Prob. 9PCh. 6.5 - Statistical Literacy What is the standard error of...Ch. 6.5 - Prob. 2PCh. 6.5 - Prob. 3PCh. 6.5 - Prob. 4PCh. 6.5 - Basic Computation: Central Limit Theorem Suppose x...Ch. 6.5 - Basic Computation: Central Limit Theorem Suppose x...Ch. 6.5 - Prob. 7PCh. 6.5 - Prob. 8PCh. 6.5 - Prob. 9PCh. 6.5 - Prob. 10PCh. 6.5 - Prob. 11PCh. 6.5 - Critical Thinking Suppose an x distribution has...Ch. 6.5 - Prob. 13PCh. 6.5 - Vital Statistics: Heights of Men The heights of...Ch. 6.5 - Prob. 15PCh. 6.5 - Medical: White Blood Cells Let x be a random...Ch. 6.5 - Wildlife: Deer Let x be a random variable that...Ch. 6.5 - Focus Problem: Impulse Buying Let x represent the...Ch. 6.5 - Finance: Templeton Funds Templeton World is a...Ch. 6.5 - Finance: European Growth Fund A European growth...Ch. 6.5 - Expand Your Knowledge: Totals Instead of Averages...Ch. 6.5 - Prob. 22PCh. 6.5 - Prob. 23PCh. 6.6 - Prob. 1PCh. 6.6 - Prob. 2PCh. 6.6 - Basic Computation: Normal Approximation to a...Ch. 6.6 - Basic Computation: Normal Approximation to a...Ch. 6.6 - Critical Thinking You need to compute the...Ch. 6.6 - Critical Thinking Consider a binomial experiment...Ch. 6.6 - In the following problems, check that it is...Ch. 6.6 - In the following problems, check that it is...Ch. 6.6 - Prob. 9PCh. 6.6 - Prob. 10PCh. 6.6 - Prob. 11PCh. 6.6 - Prob. 12PCh. 6.6 - Prob. 13PCh. 6.6 - In the following problems, check that it is...Ch. 6.6 - Prob. 15PCh. 6.6 - Prob. 17PCh. 6.6 - Prob. 18PCh. 6.6 - Prob. 19PCh. 6.6 - Basic Computation: p Distribution Suppose we have...Ch. 6.6 - Prob. 21PCh. 6 - Prob. 1CRPCh. 6 - Prob. 2CRPCh. 6 - Statistical Literacy Is a process in control if...Ch. 6 - Prob. 4CRPCh. 6 - Prob. 5CRPCh. 6 - Prob. 6CRPCh. 6 - Prob. 7CRPCh. 6 - Prob. 8CRPCh. 6 - Prob. 9CRPCh. 6 - Prob. 10CRPCh. 6 - Prob. 11CRPCh. 6 - Basic Computation: Probability Given that x is a...Ch. 6 - Prob. 13CRPCh. 6 - Prob. 14CRPCh. 6 - Prob. 15CRPCh. 6 - Prob. 16CRPCh. 6 - Prob. 17CRPCh. 6 - Prob. 18CRPCh. 6 - Prob. 19CRPCh. 6 - Prob. 20CRPCh. 6 - Prob. 21CRPCh. 6 - Prob. 22CRPCh. 6 - Prob. 23CRPCh. 6 - Prob. 24CRPCh. 6 - Prob. 25CRPCh. 6 - Prob. 26CRPCh. 6 - Break into small groups and discuss the following...Ch. 6 - Prob. 1LCCh. 6 - Prob. 2LCCh. 6 - Prob. 3LCCh. 6 - Prob. 4LCCh. 6 - Discuss each of the following topics in class or...Ch. 6 - Prob. 1UTCh. 6 - Prob. 1CURPCh. 6 - Prob. 2CURPCh. 6 - Prob. 3CURPCh. 6 - Prob. 4CURPCh. 6 - Prob. 5CURPCh. 6 - Prob. 6CURPCh. 6 - Prob. 7CURPCh. 6 - Prob. 8CURPCh. 6 - Prob. 9CURPCh. 6 - Prob. 10CURPCh. 6 - Prob. 11CURPCh. 6 - Prob. 12CURPCh. 6 - Prob. 13CURPCh. 6 - Prob. 14CURPCh. 6 - Prob. 15CURP
Knowledge Booster
Background pattern image
Statistics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
College Algebra
Algebra
ISBN:9781305115545
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Text book image
College Algebra
Algebra
ISBN:9781938168383
Author:Jay Abramson
Publisher:OpenStax
Text book image
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Continuous Probability Distributions - Basic Introduction; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=QxqxdQ_g2uw;License: Standard YouTube License, CC-BY
Probability Density Function (p.d.f.) Finding k (Part 1) | ExamSolutions; Author: ExamSolutions;https://www.youtube.com/watch?v=RsuS2ehsTDM;License: Standard YouTube License, CC-BY
Find the value of k so that the Function is a Probability Density Function; Author: The Math Sorcerer;https://www.youtube.com/watch?v=QqoCZWrVnbA;License: Standard Youtube License